Grilled Mushrooms and Onions

8oz Portabello mushrooms
1 large red onion
1 tbsp olive oil
salt and pepper

Wash mushrooms well and slice into large pieces. Quarter red onion. Heat the grill or a grill pan to medium-high and spray with cooking spray. Brush veggies with olive oil, then place on grill. Cook onions 6-7 minutes per side, mushrooms 4-5 minutes per side. Take off the grill, season with salt and pepper, then serve immediately.