Cooking Steps

• Bring a large pot of salted water to a boil. Add and cook the spaghetti according to package instructions (typically 9 to 10 minutes). Reserve 1 cup of pasta water before draining the spaghetti, do not rinse.
• In a large skillet, over medium heat, melt the unsalted butter. Add the minced garlic and red pepper flakes, stir and cook until fragrant (about 30 seconds to 1 minute).
• Add the lemon juice and ½ cup of pasta water. Once it begins to bubble, add the spinach and pasta. Toss together until spinach wilts and the sauce coats the noodles.
• Remove skillet from heat, add lemon zest, parmesan cheese, salt, and black pepper. Toss a few times before serving.