Preheat oven to 350 degrees then butter a 9" x 13" casserole dish. Place the chicken thighs in an even layer on the bottom of the dish then set aside.

Rinse spinach and let drain. Heat a large skillet over medium-high heat. Add spinach with the water clinging to the leaves and cook down until spinach has wilted and is bright green.

Drain spinach and artichokes in a colander then press as much excess liquid out of them as possible. Place on a cutting board, chop the veggies coarsely then set aside.

Place a large skillet over medium-high heat and add olive oil. Add diced onion and cook for 3–4 minutes until they begin to soften and turn translucent. Add garlic then cook for an additional 20–30 seconds. Next, add the spinach and artichokes, stirring to combine.

Season spinach and artichokes with salt and pepper and cook until completely heated through. Place mixture in a bowl then set aside.

Wipe out skillet and return to heat. Add butter and let it melt completely. Add flour and stir to combine. Allow mixture to cook for about 20 seconds before whisking in warm milk. Add basil, oregano, salt and pepper to the sauce and bring to a boil.

Reduce heat to medium-low and simmer for 2–3 minutes until thickened. Remove from heat, add shredded Monterey jack cheese and stir until completely melted. Add spinach to cheese sauce then mix well. Pour sauce over the chicken, spreading it evenly.

Sprinkle top with Parmesan cheese then bake 30–35 minutes, or until sauce is bubbly and chicken is cooked though at the thickest part. If desired, you can place under broiler for 1–2 minutes for a golden brown top.

Remove from oven and serve.