If it is any consolation , my three year old will currently only eat rice krispies, it has been this way for about 6 weeks.
6 months ago she would only eat plain pasta with a little olive oil - no cheese.
She goes through these phases.
I was a picky eater as a kid and sat for hours at the table chewing a mouthful of revolting balled up meat so I refuse to get into it with her. She eats well at school every lunchtime so it is obviously a game she’s trying to play with me.
She got sick of plain pasta and now she’s getting sick of rice krispies. She’s now beginning to ask for carrots and a serving of gorgonzola cheese on crackers. She will wolf down a stir fry and basmati rice… She eats lots of things but has these phases in-between.
I find that at the beginning of the phase I serve up what she wants - we all have pasta she wants it without the sauce: no big deal. Then after a week or so I ask what shape pasta she wants. Couple of weeks more down the line I ask which sauce she wants- tomato or pesto? Introducing a choice helps. Often she stuck to ‘no sauce’, but it became borinmg and she was seeing everyone else really enjoying their pasta and sauce.
Same goes for rice krispies. Now she will have a very small bowl as a starter and then eat what we are having. The last couple of days I have said “We are having this for dinner. You can have your cereal once you have tried what we are having.” Based on previous experience she’ll last another week before just eating what we do without the cereal dessert.
There is no fuss, no shouting, no nasty manipulation.
What worked best when she was younger was a reward. She got a (yes, just the one) smartie for finishing her dinner. She was damn delighted with it. We never said “Eat this if you want a chocolate.” or “If you don’t finish you can’t have a smartie.” But when she did finish she got a little treat. If she didn’t, she didn’t. I made sure the protions were reasonable and it was food she’d like, otherwise it seemed unfair.
There are times when I just say to her, “What do you want for dinner?” and she gets whatever she asks for. This is also true when I am about to prepare a meal and she comes in saying she wants cereal. I’ll cook for everyone else and she has cereal. When she heads me off at the pass, I let her have it her way. These fads will pass…