Preheat oven to 350 degrees and melt butter in a 9x13 in pan.
Beat eggs in a medium bowl.
Add milk, flour, baking powder and salt. Beat until well blended.
Stir in spinach, cheese and bell pepper mix well. Spread mixture over melted butter in pan.
Bake 40 to 35 minutes or until set. Let stand 10 minutes before cutting into triangles or squares.
You can make this ahead, freeze in and then reheat it. Here's how. After baking cool completely and cut into squares. Transfer squares to a cookie sheet and place in the freezer until all squares are frozen solid. Place frozen squares in a food storage bag. To reheat. Place frozen squares on a cookie sheet and place in a 325 degree oven for 15 minutes. Enjoy!