If you have a very picky eater in your family, meal planning can be pretty disheartening. It can feel like you are serving the same few meals on rotation OR perhaps you are stuck in the trap of cooking up alternatives when your child rejects what you have served?
I recommend following two key principles when it comes to planning your meals. First, use 'family style' serving, where all the elements of a meal are put in serving bowls in the middle of the table, and everyone serves themselves. If you're not familiar with this approach, you can read more about it in this post, where I explain why family style meals are so great for picky eaters.
Once you are serving family style, you can schedule whatever meals you want your whole family to be eating, regardless of your child's food preferences. You like Thai green curry? Plan it in. Fancy salmon but your child hates fish? That's fine, you can still have it and your child will actually benefit from being exposed to it even if they don't touch a mouthful.
When I say 'regardless of your child's food preferences' it might sound like I'm suggesting you ignore these. Far from it. The second principle when it comes to meal planning, is to always include a couple of your child's safe foods (foods they will reliably accept).
I am not a dietitian or nutritionist (my expertise is in the psychological, emotional and behavioural aspects of children's eating) so I don't offer nutritional advice. However, it is common sense to think about your child's nutritional needs in a 'big picture' kind of way rather than meal by meal. I suggest you write down their safe foods, split them into nutritional groups and then plan them across the week in a balanced fashion, with as much variety as possible.
Sometimes this involves forgetting what you know about what is appropriate to eat when. If your child's only fibre (fiber) is in the form of a breakfast cereal, it's fine to serve some in a bowl with their evening meal sometimes. Of course, it's great to match your choice of safe food to the other food on the menu too. For example, if your child eats plain noodles, serve them alongside a stir-fry. A good fit is not always possible though, and you may need to let go of some of your expectations about what constitutes a reasonable meal.
I recommend getting a clear idea of what your child's nutritional needs are then planning their safe foods into your weekly meals in an attempt to match this as closely as possible. There are lots of online resources offering information on childhood nutrition. Make sure the source is reliable, and if in doubt, consult a dietitian.
Before you can help your child access a more varied diet, it's very important to work on making meals relaxed and enjoyable for them. Making sure you always include a couple of your child's safe foods (and this goes for snacks too) is one of the things you can do to help achieve this goal. It will help reduce your child's anxiety because they can trust that there will always be something available for them to eat. It will lower your anxiety because you will know this too. If everyone is happy and the environment is pressure-free, you are doing a huge amount to support your child's relationship with food.