Stuffed Baby Portobello Mushrooms

I love Costco, but when there are only two members in your family, it's difficult to use Costco quantities without everything spoiling. That's why I buy carefully -- I buy foods that last a long time, such as mini bell peppers, olive oil and chicken stock. But yesterday I just couldn't resist the baby portobello mushrooms in the refrigerated produce room. Also too delectable to avoid -- the Costco rotisserie chicken. Such heavenly flavor for only $5 and there's so much you can do with the leftovers.
This recipe I threw together in about 20 minutes. It uses some chicken leftovers and makes good use of my perfect mushrooms. These make colorful appetizers, but I was craving them as my main meal. They were delish!

Ingredients:
3 mini bell peppers (red, yellow and orange) or 1/4 of a bell pepper
1/8 of an onion
1 clove of garlic (I was out, but I would normally add this with the onion)
about 12 mini portobello mushrooms (crimini or buttons would work too), stems removed and saved
olive oil
salt and pepper
1 tbs fresh chopped oregano
2 tbs bread crumbs
2 thick slices of roasted chicken breast
1/4 cup parmesan cheese, grated

Directions:
Preheat oven to 375 degrees.
Carefully remove the stems from each mushroom and with a melon baller, scoop out some of the flesh inside each mushroom so there's room to stuff. Save what you scoop.

In a mini food processor, pulse the peppers, onion and mushroom stems and innards till finely chopped. In a small frying pan, heat up about a tablespoon of olive oil. Add the peppers, onion, garlic, mushroom innards, oregano, salt and pepper. Saute till everything is softened, about 5 minutes. Meanwhile, finely chop the chicken.
Transfer the cooked ingredients to a bowl and combine the chicken, bread crumbs and half the cheese. In a small baking dish, fill each mushroom cap with the mixture so it mounds up on top. Top with shredded parmesan cheese and bake for 15-20 minutes or until lightly browned on top.