In a large pot with boiling salted water cook penne pasta until al dente. Drain.
Meanwhile, in a large skillet cook sausage until brown. Remove from pan. Saute the red onion and garlic in the olive oil until soft and transparent. Add the oregano, salt, ground black pepper, red pepper flakes, 1/2 of the wine, yellow bell pepper, red bell pepper, zucchini, mushrooms, and saute until tender. Add remaining wine and chicken stock and cook until liquid has reduced to a thick sauce, about 20 minutes.
After sauce has reduced, add cooked sausage and thawed peas to the sauce and stir to heat through.
Toss pasta with the sauce to coat evenly. Sprinkle with the grated Parmesan cheese. Serve warm.
