Perfect crumble recipe please

[bananaskin123]

We have an apple tree which has loads of apples much of which I've stewed and sometimes add to breakfast. They are OK but definitely not Bramleys. Decided to make an apple and blackberry crumble this afternoon with some more windfalls. The crumble was a Good Food recipe which consisted of butter, sugar and all the usual things but suggested a tablespoon of rolled oats and 1 of demerara sugar added before cooking. Cooked at 170 fan as advised. Maybe I used too many apples, recipe called for 1 lb and mine came to 2 lbs but I didn't double the crumble mixture so its patchy and honestly not that good. Any perfect never fail recipes for crumble please and do the apples you use really make a difference

If you’re using cooking apples, soften them in a saucepan along with a couple of tbsps of caster sugar, a splash of water and some lemon juice. They only need a few minutes over a low heat.
If you’re using dessert apples, I’d skip this step and not bother with the sugar as they’re sweet enough already.
A good topping ratio is 2 flour : 1 butter : 1 sugar. Of course you can always add more sugar or less - it doesn’t seem to affect the texture. 240g of crumble topping will cover a crumble to serve 4 (I use about 850g of fruit for a crumble for 4). That means 120g flour, 60g butter and 60g sugar.
Make sure you use proper dairy butter. No exceptions.
If you’re going to add oats, scatter them on the top rather than mix them into the crumble so they toast, rather than cook into a stodgy porridge below

Toast the crumble mixture separately first