Preheat oven to 325 degrees F. Spray muffin tin with cooking spray.

Heat a non-stick skillet over medium, add sausage and cook until no longer pink; stirring to break up pieces.  Remove from skillet.

Chop onion, pepper and mushrooms; add oil to skillet used for sausage and allow to heat.  Add chopped vegetables and cook until softened, approximately 6-7 minutes.

Add vegetables to meat along with cheese and pepper; stir together and set aside.

Whisk eggs and milk in a bowl; place a small amount of spinach into each muffin tin, pour eggs evenly into muffin tins over spinach, top off with sausage mixture.  Bake for 20-25 minutes, until the tops begin to brown.

Serve with grapes.