1Heat oven to 400°F. Spray bottoms and sides of 12 regular-size muffin cups with cooking spray. (Spray will work better than greasing or using paper muffin liners.)
2Beat eggs slightly in medium bowl with fork. Stir in Bisquick mix, milk and oil just until moistened. Stir in 3/4 cup of the cheese and the ham. Divide batter evenly among muffin cups. Sprinkle remaining 1/4 cup cheese evenly over tops of muffins.
3Bake 18 to 20 minutes or until light golden brown. Immediately remove from pan. Serve warm. Wrap and refrigerate any remaining muffins.