Cook pasta according to package directions. Heat olive oil in a large skillet over medium heat. Add bell pepper and saute for 5 minutes. Add 1/2 tsp of salt, 1/4 tsp pepper, and cook for another 5 minutes.
Add garlic and cook for about 1 minute, then mix the garlic into the rest of the mixture and cook until zucchini is soft. Add lemon juice and a pinch of red pepper. Taste and add more salt if necessary.