I've found a great recipe for strawberry filling using fresh strawberries. The secret with this recipe is to cook it long enough so that it will reduce and gel properly when cooled. I had to make it 3 times before I got the right consistency.
You're going to start with some fresh red strawberries. It usually takes 1 1/2 of the larger containers from the grocery store.
Cut the caps and stems off and chop the strawberries into very coarse pieces. You will need 2 1/2 cups
Mix the strawberries, 1/2 cup sugar and 2 1/2 tablespoons of cornstarch in a medium heavy saucepan.
Bring the ingredients to a boil over medium heat, stirring constantly. Crush the pieces of strawberry against the sides of the pan with your spoon while cooking. This will release the juices into your mixture.
Once your mixture has reached a boil, continue boiling for 2 1/2 minutes to thicken. Make sure to constantly stir so that it doesn't burn on the bottom. Your mixture will be chunky.
Once your mixture is thick, pour into a bowl, cover and cool completely in the fridge. I usually cook the day before I need it so it has ample time to cool and thicken a little more. When filling your cake, make sure to put your buttercream (frosting) dam around the edges of your tier so that the filling won't ooze out the sides of your cake after you've added other layers.
Deeeeelicious! Also is great on ice-cream :) Enjoy!!