Bring a large pot of salted water to a boil and cook the linguine according to package directions until al dente.
While the pasta cooks, season the chicken breast with sea salt and black pepper on both sides.
Heat the olive oil in a large skillet over medium-high heat and sear the chicken for 5-6 minutes per side until fully cooked through.
Remove the chicken from the pan, let it rest for a few minutes, then slice into thin strips.
In the same skillet, add the minced garlic and halved cherry tomatoes, sautéing for 2 minutes until the tomatoes begin to soften.
Whisk together the Greek yogurt and basil pesto in a small bowl until smooth.
Reduce the skillet heat to low, add the cooked linguine, baby spinach, and the pesto-yogurt mixture.
Toss everything together gently until the spinach is wilted and the pasta is coated in a creamy sauce.
Add the sliced chicken back into the pan, toss once more, and serve immediately.