Bring a large pot of salted water to a boil. Cook spaghetti according to package instructions until al dente. Reserve 1/4 cup of pasta water before draining.

Season chicken breasts with salt and pepper. Heat olive oil in a large skillet over medium-high heat. Cook chicken for 5–6 minutes per side or until golden brown and fully cooked (internal temperature should reach 165°F). Remove from skillet, let rest, then slice thinly.

In the same skillet, reduce heat to medium and melt butter. Add minced garlic and sauté for 1 minute until fragrant. Stir in lemon zest and juice, then add a splash of reserved pasta water. Simmer for 2–3 minutes to slightly thicken the sauce.

Add the drained spaghetti to the skillet and toss well to coat. Add more pasta water if needed to loosen the sauce.

Return the sliced chicken to the skillet and gently toss everything together.

Plate the pasta and top each serving with a ball of burrata. Garnish with fresh parsley, optional red pepper flakes, and serve immediately.