Get a really good breakfast down them with as many ‘extras’ as you can to up nutrition e.g.
-Greek yoghurt with berries or banana or grated apple, add a little nut butter or sunflower or pumpkin seed butter, you could also add ground almonds or ground other nuts like walnuts. You can buy milled mixed seeds - Aldi have a good selection. You could also mix in some of the fruit pouch if your baby enjoys that.
—Toast fingers with cream cheese and raspberries, or peanut butter, mashed up avocado, or a little bit of scrambled egg - you can progress to eggy bread, or other kinds of cooked breakfast as you go on.
-Porridge - get the sachets if you feel more confident with that, but it’s really easy (and cheaper) to use the rolled oats, with milk and add different toppings to pack the nutrition in - as above really, different soft fruits or dried fruits, nut butter or ground almonds. My dd loves grated apple, grated carrot, a few sultanas, a teaspoon of ground cinnamon and a bit of nut butter - we call it carrot cake porridge and sometimes we have it for an easy dinner too.
Lunches can be a repeat of a lot of the breakfast ideas, assuming you did a different breakfast -
-Beans on toast (you can get the low sugar ones but I’ve always preferred to get the organic normal ones and just not serve them as often)
-Mash up some butter beans with avocado and serve on toast, a cracker, wraps
-Decent quality shop bought hummus - check ingredients and go for the best one - with carrot and cucumber sticks, a few breadsticks, couple of cubes of cheese, a sliced apple
-Buy the most minimally processed wraps you can, spread with decent toppings, choose a few from hummus, cream cheese, grated carrot, grated cucumber, decent ham or cooked chicken; roll them up and slice into pinwheels, serve with extra veg sticks, cherry tomatoes or fruit
-Boil pasta, add frozen peas for last few mins, stir through some cream cheese and tomato purée. Or you could just drizzle the cooked pasta and peas with olive oil or mix in butter and top with grated cheese. Or mix cooked pasta with tinned tuna, sweetcorn and Greek yoghurt.
-Buy a bag of pre chopped vegetables for soup, boil in the pan with a low salt stock cube and a tablespoon or so of red lentils - often the pre chopped mixes come with some anyway, or they might have barley or other grains. Bring to boil and simmer for 20 mins or so (or follow instructions on pack), blitz with a stick blender. When DD was very little I’d often add a bit of couscous to hers whilst it was hot, leave it to cool down 5-6 mins or so and the couscous really thickened it up to make it easier for her.
Dinner
-Any of the above
-Jacket potatoes with different toppings
-Frozen fish fillets - brush a sheet of foil with some oil, put the fish on - you could squeeze some lemon over and any herbs - in oven or air fryer for about 20 mins but follow pack instructions - mash (could be the ready made to start with) and vegetables, frozen veg is fine
-Chicken breasts - you can slice in half and pan fry, or bake in the oven/ do in air fryer, they’re also really easy to do in a slow cooker and then you can use forks to kind of shred them and add to any wraps/ sandwiches/ pasta dishes etc
-Not always great for the budget but there are some good convenience options out there that will still have really good nutrients in them, we like the tilda kids micro rice packets, they have at least 1 portion of veg in, and then you can add a protein (chicken, sausage, some beans or chickpeas) and extra vegetables. Or you can get mixed grains and pulses in microwave sachets.
-Ready made mash often doesn’t have any nasties in it if you check the ingredients - get one made with different root veg for a bit or variety. or but the pre diced butternut squash and sweet potato - boil, drain and mash with butter and black pepper
I reckon if you did one or two of these each day you’d be doing pretty well and your DC would be getting lots of what they need, and hopefully you can build your confidence from there. But also - do you have a DP in the equation - can they not share some of the load?