Prep the mushrooms
Wipe each mushroom clean with a damp cloth. Snap off stems sideways to keep the caps intact and hollow. If a cap feels small, press the sides gently inward to widen the cavity — stuffing will hold it together.
Season the caps
Toss the mushroom caps with 1 tsp olive oil, ⅛ tsp salt, ⅛ tsp pepper, and 1 tsp balsamic vinegar. Set them aside while you make the filling. The vinegar adds brightness and a slight caramel note when cooked.
Make the filling
Combine bell pepper, onion, cilantro, jalapeño, ⅓–½ cup shredded vegan mozzarella, coriander, salt, and paprika in a bowl. Mix thoroughly. If you like a melty center, go toward the ½ cup end.
Stuff generously
Use a teaspoon to pack each cap with filling. Press the mixture in so the mushroom looks full — don’t be shy. The filling wilts and melts down during cooking.
Air-fry (my go-to method)
Arrange mushrooms in the air fryer basket without overcrowding. Cook at 320°F for 9–10 minutes for small caps, or 10 minutes for regular size. Let them rest 5 minutes before serving so the filling sets slightly.
Alternative methods:
Air fryer lid on instant pot trivet: layer in a mesh basket and cook 12 minutes at 325°F.
Oven: Preheat to 400°F, bake on a lined sheet 16–18 minutes until the cheese browns and caps darken.