Line a 9-inch pieplate with pastry; fold edges under and flute. Prick the bottom and sides of pastry with a fork. Combine egg yolk and water; stir well. Brush egg yolk mixture over pastry. Bake at 400 degrees for 10 minutes; set aside.
Cook broccoli in a small amount of boiling water until crisp-tender; set aside.
Saute sausage, green pepper, and chopped onion in melted butter in a large skillet over medium heat until the vegetables are tender; drain well. Add flour to the sausage mixture, stirring well. Remove from heat.
Combine eggs and half-and-half in a medium bowl; beat well with a wire whisk until blended.
Sprinkle 1 cup of shredded cheese over the bottom of the pastry shell; top with broccoli and kielbasa mixture. Sprinkle with the remaining 1 cup of cheese. Pour the egg mixture over the cheese; sprinkle with parsley and garlic salt.
Bake, uncovered, at 375° for 30 to 40 minutes or until set and lightly browned. Let stand for 5 minutes before serving.