1 lb. Pappardelle's Lemon Basil Fettuccine
1 onion, finely diced
2 lb. zucchini, sliced into 1/4" pieces
1 tsp. salt, plus more for seasoning
1 tsp. pepper
3 tbsp. extra-virgin olive oil
2 cloves garlic, minced
8 oz. ricotta
Zest of 1 lemon
2 oz. grated Pecorino Romano
2 cups loosely packed basil
Pinch of crushed red pepper flakes