Place all ingredients at room temperature. Preheat the oven to 400 degrees F. Over low heat mix together the butter and flour, add the strawberries and stir together to make a thick sauce. Add the liqueur and food coloring. Separate the eggs, adding the yolks one by one to the strawberry sauce. Beat the whites in a clean dry bowl until stiff, then fold them gently and lightly into the strawberry mixture and turn into a buttered soufflé dish. Place in the oven and immediately reduce the heat to 375 degrees F. Bake for just 80 minutes; serve with whipped cream and, if you wish, fresh strawberry sauce.