Slow Cooker Chicken and Rice Casserole

Name: Slow Cooker Chicken and Rice Casserole
Ingredients: 2 pounds bone-in, skin-on chicken thighs (or 1 1/2 pounds boneless, skin-on chicken thighs); Kosher salt; 2 tablespoons extra virgin olive oil; 4 cups sliced yellow onion, 1/4-inch-thick slices, sliced root to tip (about 2 large onions ); 1 teaspoon ground cumin; 1/4 teaspoon ground cinnamon; 4 teaspoons finely chopped garlic (about 4 cloves); 2 cups raw basmati long-grain rice; 1 cup diced canned (or fresh) tomatoes; 1/2 cup frozen peas, optional; 1 1/2 cups chicken stock; 3/4 teaspoon black pepper; 2 bay leaves