In a large mixing bowl cream together the butter and sugar until light and fluffy. With a mixer, beat in the egg, strawberry preserves and vanilla. Add in the flour, baking powder and salt.
Mix until just combined. The dough will be crumbly.
Divide the dough into 12 equal portions and form each portion into a ball. Just until it comes together.
Refrigerate for at least 30 minutes.
Meanwhile preheat the oven to 375 degrees.
Bake the cookies for 15-18 minutes on a baking sheet. You want the edges to just be golden brown, but the inside of the cookies to stay chewy. Cool 5 minutes and then transfer to a rack to cool completely.
Meanwhile make the buttercream for topping.
Using a hand mixer or stand mixer whip the butter until fluffy.
Add in the powdered sugar and beat to combine.
Add a splash of milk or coffee creamer if the buttercream is too thick.
Spread the frosting carefully on the cookies.
Next, make the strawberry crunch topping.
In a large ziplock bag crush the oreos into crumbs.
Add the oreo crumbs, jello mix and butter to a bowl and stir to combine.
Press the strawberry crunch topping evenly all over the cookies.
Serve and enjoy!