Saute onion and green peppers in butter until tender. Set aside and wipe out dutch. For crust combine flour and salt. Cut in shortening until a fine texture is reached. Add water and mix lightly. Do not over mix! Roll flat (1/8 inch thick) and lay in the bottom of dutch. Press crust onto sides and flute with a fork. Cover and bake 10-15 minutes or until golden brown. Meanwhile, combine all filling ingredients in a separate bowl and mix well. Pour into crust and sprinkle with a handful of grated cheddar. Cook 25-35 minutes or until knife inserted in center comes out clean. Garnish as desired.