These can be made a day in advance. However, I recommend you pre-cook the bell peppers as outlined in Step 1 of the recipe card below. Follow all of the instructions, aside from Step 6. Store covered in the fridge overnight, let the peppers rest at room temperature while the air fryer preheats, then cook. You may need to add some additional cooking time, about 5-10 minutes because the peppers will be going in the air fryer cool.