In a large pan, heat oil over medium heat, add oil and sauté onion until translucent and tender. Add the sausage and break up until cooked through, about 5 minutes. Add the spinach and cook until wilted, about 2 to 3 minutes. Set aside.
In a large bowl, whisk together the flour, baking powder, baking soda, salt, and pepper.
In a separate medium bowl, whisk together the yogurt, coconut oil, and eggs.
Add the dry ingredients to the wet and stir until just combined, don’t overmix.
Stir in 3/4 cup cheese, apples, and cooked sausage.
Transfer the batter to the jumbo muffin tin, filling about 3/4th full, and topping with cheese and chives, if using.
Bake 5 minutes at 400F, lower the heat to 350F and bake for 20 minutes or until the tops are golden and a toothpick comes out clean.
Allow cooling 5 minutes before removing from the muffin tin and enjoying.