Heat the olive oil in the skillet, saucepan, or stockpot. Add the onion and 1/2 teaspoon Kosher salt and saute over medium heat until soft and light golden brown. add the garlic and continue to saute for a minute. Remove to a plate or bowl.
Add the chicken thighs to the pan and salt with remaining salt and 1/8 teaspoon of pepper. Brown on each side over medium high heat.
Add the tomatoes, water, tomato paste, sun-dried tomatoes, and basil. Add the onion mixture back in. Stir and set to simmer for 1 ½-2 hours, covered with the lid cracked over very low heat. Stir occasionally breaking the chicken pieces apart. Add 1/4 cup of additional water if the sauce is getting too thick. Add more salt and pepper to taste.
Heat the pasta water to boiling. Cook your gluten free pasta to "al dente" (just slightly underdone). Reserve a 3/4 cup gluten free pasta water spooning out from the cooking pasta. Drain the pasta but do not rinse. Add a 1/4 cup or more of the pasta water back in with enough sauce to coat and cover the pasta.
Serve immediately in individual dishes or a larger serving dish. Top with a large spoon of ricotta cheese and shaved or grated parmesan cheese. Add parsley or basil to the top of the dishes.