Bring a large pot of salted water to a boil and cook the linguine until al dente, reserving 1/4 cup of the pasta water before draining.
While the pasta cooks, season the chicken breast with sea salt and black pepper.
Heat olive oil in a large skillet over medium-high heat and sear the chicken until golden brown and cooked through, about 5-6 minutes per side.
Remove chicken from the skillet, let it rest for a few minutes, then slice into thin strips.
In the same skillet, add the minced garlic and sauté for 30 seconds until fragrant, then add the fresh spinach and cook until just wilted.
Reduce the heat to low and stir in the basil pesto, plain Greek yogurt, and reserved pasta water to create a smooth, creamy sauce.
Return the chicken and cooked linguine to the skillet, tossing everything together until the pasta is thoroughly coated in the velvety sauce.
Serve immediately topped with a sprinkle of parmesan cheese for a sharp, salty finish.