Heat oil in heavy Dutch oven over medium high heat.
Add both bell peppers and garlic.
Saute until peppers begin to soften, about 4 minutes.
Mix in peperoncini and basil, then tomatoes.
Simmer until sauce reduces slightly, breaking up tomatoes with back of spoon, about 5 minutes.
Add pasta and toss until sauce coats pasta.
Add feta and toss mixture to blend.