Boil the pasta: Salt a large pot of water and cook pasta to al dente. Reserve 1 cup of hot pasta water before draining.
Sauté garlic: In a skillet, warm 1 teaspoon olive oil over low heat.
Add minced garlic and cook 30–60 seconds until fragrant. Don’t brown it.
Blend the sauce base: In a blender, add cottage cheese, Greek yogurt, half the Parmesan, most of the reserved pasta water (start with 1/2 cup), lemon zest, a squeeze of lemon juice, salt, and pepper. Blend until completely smooth and glossy.
Combine and gently warm: Pour the blended sauce into the skillet with the garlic.
Heat on low, stirring, until warm and slightly thickened, 2–3 minutes. If it’s too thick, add more pasta water a little at a time.
Toss the pasta: Add drained pasta to the skillet and toss until every strand is coated. Stir in remaining Parmesan.
Taste and adjust salt, pepper, and lemon.
Finish and serve: Sprinkle red pepper flakes and chopped parsley. Add cooked chicken, shrimp, or peas if using. Serve right away while silky and hot.