Cut a horizontal slit through the center of the chicken to form a pocket.
Heat 1 tablespoon of olive oil in a large skillet to medium heat.
Next, add onion, and cook 3 minutes, stirring frequently. Add garlic and cook one minute more.
After that, add spinach, and sauté until wilted, about two minutes.
Season to taste with salt and pepper
Transfer to a bowl and allow to cool slightly. Stir in cheeses.
Stuff the chicken pockets with the spinach and cheese mixture using toothpicks to secure.
In a small dish, mix together paprika, salt, and pepper. Sprinkle over the chicken.
Heat the remaining tablespoon of avocado oil in a large skillet over medium-high heat.
Add chicken and cook until golden brown and cooked through, about 5 to 7 minutes per side.
Remove the chicken when it is 160 degrees. Tent and let it rest for 5 to 10 minutes.