Bring a large pot of salted water to a boil and cook the brown rice linguine according to package directions until al dente, reserving 2 tablespoons of pasta water before draining.
Slice the chicken breast into bite-sized strips and season evenly with sea salt, black pepper, and garlic powder.
Heat the olive oil in a large skillet over medium-high heat and sauté the chicken for 5-6 minutes until golden brown and cooked through.
Add the cherry tomatoes to the skillet and cook for 2-3 minutes until they begin to soften and blister.
Stir in the baby spinach and cook for 1 minute just until wilted, then remove the skillet from the heat.
In a small bowl, whisk together the basil pesto and Greek yogurt until smooth and well combined.
Add the cooked linguine, the pesto-yogurt mixture, and the reserved pasta water to the skillet.
Toss everything together until the pasta is thoroughly coated in the creamy sauce and serve immediately.