Bring a pot of salted water to a boil and cook the chickpea spaghetti according to package directions, reserving 2 tablespoons of pasta water before draining.
Season the chicken breast with half of the sea salt and black pepper.
Heat olive oil in a skillet over medium-high heat and sear the chicken until golden and cooked through, then set aside to rest before slicing.
In the same skillet, reduce heat to medium and sauté the minced garlic until fragrant, about 1 minute.
Whisk together the Greek yogurt and grated parmesan in a small bowl.
Add the cooked pasta and baby spinach to the skillet, tossing until the spinach begins to wilt.
Remove the skillet from heat and stir in the yogurt mixture and the reserved pasta water to create a smooth, creamy sauce.
Top the pasta with the sliced chicken and the remaining sea salt and black pepper before serving.