1. Mix tomatoes, corn, black beans, red onion with approx. 1/2 tsp of ground cumin, fresh parsley (cilantro if you fancy), lemon juice.
2. Put a couple of handfuls of spinach on foil, top with seasoned filling:
3. Toss the tilapia fillet on top:
Wrap the foil up, sealing the edges (I put another piece on top because my bottom piece was too small to wrap), stick it in a 400F oven (I used my toaster oven at 450) for 20-25 min or until fish flakey.