Cook the pasta. Bring a pot of salted water to a boil. Cook pasta until al dente. Reserve half a cup of the starchy pasta water before draining.
Make the creamy yogurt sauce. In a skillet over low heat, warm olive oil and garlic for one minute until fragrant. Turn the heat off. Add Greek yogurt, parmesan, lemon juice, onion powder, salt and pepper. Mix gently. Do not heat the yogurt directly or it may curdle.
Add pasta water. Pour in 1/4 cup of hot pasta water and whisk until the sauce becomes glossy and smooth. Add a splash more if needed. The starchy water helps the sauce stay silky without cream.
Add the protein. Add cooked chicken breast or chickpeas to the skillet and fold them into the sauce.
Toss with pasta. Add drained pasta to the skillet. Toss until everything is coated in the creamy yogurt sauce.
Serve. Serve warm with extra parmesan, basil and chili flakes. Enjoy immediately.