Butter 4 small ramekins and set aside. Preheat your oven to 350 degrees.
Beat the butter and sugar in a medium bowl until combined. Sift in flour. Stir in the milk, egg yolks and 1/4 cup of the strawberry mixture.
In another bowl, whisk the egg whites until stiff. Fold in gently into the batter.
Place the 4 strawberry slices on the sides of the butter ramekins. Then pour the batter, billing them up to 2/3 height, leaving some room to allow the souffle to expand. Bake for about 15 minutes or until the top is light golden brown and the souffle separates from the sides.