Marys Succotash

Name: Mary's Succotash
Ingredients: 3 cups corn kernels, cut from fresh ears of corn; 2 cups green beans, cut into ~1/4 length; 1/2 cup somewhat finely chopped shallots or sweet onions; 1/2 cup small diced red bell peppers; 3 tablespoons good quality butter, plus an extra 1Tb if needed.; salt & pepper