Failed roast potatoes. Have I lost it?

[PollyOrange]

Done roasties on Christmas Day and also the week before and both batches weee awful. I've previously been good at roast potatoes but no more.
Maris piper potatoes. Par boiled for 15 mins from cold water. Mix of olive and rapeseed oil. (No animal fats ). The oil was hot or so I thought. Oven 180 fan. They just didn't seem to sizzle or crisp up no heated oil up and put more on but only a few were crispy.
Could they have been crowded ?
Ideas welcome please. I feel scared I've lost it.

Sometimes a few small elements go a bit wrong resulting in them not working out so well
possibly a bit overcrowded as you say?
possibly you had more items in the oven or the door was opened more than usual? Resulting in temp being a bit lower.
maybe a natural variance in the potato even if the same variety
I only parboil for 5 minutes. Drain, rough them up. I’d have the fan oven 200 to start and a thin layer of oil really sizzling
get the pan back in quick so it doesn’t cool down.

You will have to keep trying until you get them right!

Parboil for 5-10 once boiling depending on size of potato.
Leave to dry well. THIS IS CRUCIAL. Wet potatoes don’t crisp up the same.
Salty oil, hot.
Space well so not touching.
Turn a few times.

I actually only used to boil for 5 mins but more recently done longer as advertised by Jamie and others. I need to make several more batches clearly.

Don't use olive oil, the smoke point is too low. And don't use rapeseed oil or any seed oil for that matter, they are all terrible. Use beef fat or goose fat. Make sure the potatoes are dry before they go into the fat.

You need to let them dry really well and either rough up well or dredge them and shake with a couple of tablespoons of semolina or flour.

Personally I wouldn't use olive oil for roasties but just use Rapeseed.

The other thing is whether the oven is hot enough as 180C fan is around 200 no fan - I think. But I crank mine (non fan) up to 225-230C for roasties

After parboiling shake in plain flour. Bake on baking sheet so air can flow around them (they shouldn't touch each other).

Sadly don't eat those as I don't eat meat but I can imagine delicious if you do

Higher oven temperature and make sure you’re not cooking anything else in the oven that creates steam.

I heat up my oil/fat in a roasting tray on the hob first.

You need to give them a dusting of flour after you pat boil them. I also try to par boil them to the point where they are a little bit sticky and fluffy. Also, goose fat is hands down the best, in my opinion, but going off your post I’m guessing you don’t use animal products?

Parboil for 10 mins, drain and leave in the pan to dry for a few mins. Put the lid on the pan and shake to rough up the edges.

I use rapeseed or vegetable oil. Preheat oven to 200 degrees, heat the oil for 10 mins, tip the potatoes into the hot oil and spoon oil over each potato. Make sure the potatoes are well spread out and not touching.

Cook for 45 mins.

Right. I'm off to buy spuds and try again

Halfway through, use a fork or potato masher to just push them down and then put back in.

Makes the edges really crispy.

I'd go hotter and I wouldn't use any olive oil - it's not really suitable for cooking at high temperatures. And I sprinkle on a bit of flour or semolina before putting the parboiled potatoes in the hot fat.

As pp have said, you need to make sure the potatoes are dry after parboiling or they won’t crisp up. And the oven temperature is low at 180, I go for 220 (not fan).

Just roast them for longer. I prefer them done at a lower temp for longer as you get lovely caramelised bits.

Are you leaving them in the oven for long enough? I found i was expecting them to be done in 45 mins or so but 1 hour plus, maybe up to 1 1/2 hours gets them really crispy.

It's not the type of oil unless it was extra virgin. Either your spuds weren't dry enough, or the oil/oven wasn't hot enough, or the pan was too crowded, or a combination.
There was a thread here on Christmas eve, the OP there had over boiled hers, or so she thought. She was encouraged to crack on and roast them and they turned out fine. By coincidence I did the same and mine were, apparently, the best I'd ever made. In olive oil and sunflower oil!

I use olive oil for roast potatoes because that's what Heston Blumenthal uses! Always works well for me, you don't need animal fat.

I find they often take longer than you'd expect to get brown and crispy. 180 is on the low side, I usually do them at closer to 200.

Coconut oil is supposed to be closest to goose fat

1. do you normally use maris piper? Were both batches from the same bag? The potatoes make a huge difference (I like king Edwards personally)

2. possibly the oven needed to be a bit hotter? If in doubt, just leave them in a bit longer, they usually come good in the end!

Mine haven’t been great either recently, turned out the oven wasn’t at the temperature it said it was, so 200 was really 180, cranked it up to 225, all good.

I would say slightly higher oven temp, and no olive oil. Also, I don’t heat the oil…… Mine come out crispy. Also parboil for about 15 mins and leave in the colander for quite a while to dry out.

Op, nobody makes roast potatoes like me! They are perfect every single time. Probably about the only cooking I do that is, but hey!

I follow the following steps:

1.parboil for 5 minutes. This means literally dropping into bubbling water (mind the splashes!)

1. Cut potatoes into small portions first. A medium potato will get cut in thirds, a small halved, and a large quartered.
2. Don't put anything in the boiling water other than cut potatoes
3. Always use a timer.
4. Drain water immediately, then put the lid back on the saucepan and shake vigorously for about 3 or 4 shakes. You can see the potatoes fluff up.
5. Transfer to preheated sunflower oil. Rapeseed would also work.
6. Cook for around 45-60 minutes, turning at least once if not twice. This is the only variable part that will be trial and error. I always cook with the fan assisted oven already set to the chicken-cooking temperature (180°c).

They are golden and crisp and have lovely soft steaming hot insides every single time.

180 fan is a tad too low. I don't parboil mine for any longer than 10 mins. I don't put them in cold water to start with either. Peel, put in pan, pour on boiling water from kettle, bring back to boil, turn off after max 10 mins and drain straight away.

While the potatoes are boiling bring the oven to temperature (220 C or 200 fan), and heat the tray and fat up too. I try to use goose fat but will use sunflower oil (just not olive oil as it smokes at that temperature). Sometimes I put a garlic clove or two in with the fat for a few mins to flavour it.

If you've got the temp of the fat right, when you (very carefully!) pour the drained potatoes in the fat will sizzle like a maniac. Turn them all individually so they're covered in fat then put back in the oven for 45 mins min, turning every so often. When they're done you can put them into a serving dish and sprinkle with salt and they will keep for a bit longer.

I do find that a very deep, overcrowded roasting tray isn't the best for crispy roasts.

And definitely don't put potatoes around the meat which should be cooking at a much lower temperature. MIL does them like that and honestly they are barely different to boiled potatoes. Nice enough flavour because of the meat juices but not at all crunchy.