1 cup icing sugar
1 tsp. vanilla
3 cups flour
1 cup butter
Leftover strawberry juice
If you used frozen strawberries and have left over juice put it in a pot on medium to low heat. Measure the amount of juice and add the equivalent of half of the amount in sugar. Cover and let simmer and reduce for about an hour, until the juice thickens and has a sticky consistency. Let it cool at room temperature before putting in the fridge.
For the shortbread, ceam the butter and icing sugar with a hand mixer until fluffy. Add cornstarch and vanilla, then add the flour one cup at a time. Condense the dough in a large ball, cover with plastic wrap and put in the fridge for 30 minutes so it firms.
To get the cup shape I hand rolled the batter into balls approximately 1 inch in diameter. Kneed the batter so it doesn't crack and use your index finger to hollow out the center. Do this twice for each muffin (for the top and bottom).
Add about half of a teaspoon of reduction to one of the shortbread cups. Invert the other cup on top and smooth the batter of the crack between the two. Try not to let the strawberry leak out. Gently roll it into a ball in your hand and place in the mini cupcake cups. Bake at 325 degrees for 20 minutes or until the tops slightly crack.