Butternut Squash Casserole

INGREDIENTS

• 1 butternut squash
• 1 cup white sugar
• 1 1/2 cups milk
• 1 teaspoon vanilla extract
• 1 pinch salt
• 2 tablespoons all-purpose flour
• 3 eggs
• 1/4 cup margarine, melted
• TOPPING
• 1/2 (16 ounce) package vanilla wafers, crushed
• 1/2 cup margarine, melted
• 1 cup brown sugar