For the pie:
For the streusel topping:
- Place the watermelon rind and ¼ cup of the sugar in a medium pot (set aside the rest of this sugar for the pie filling). Fill the pot with water to cover the watermelon rind by a few inches. Bring the pot to a boil over medium heat, then reduce to low heat and cook at a low boil for 25 minutes, until the rind is soft and sweet. Drain the water from the pot and set aside the rind in a large mixing bowl.
- Meanwhile, preheat the oven to 425 degrees F, and start to prepare the crust. Place the crust on a large pastry mat (or cutting board) and use a 3-inch biscuit cutter to cut 12 circles. You’ll need to combine the scraps together to get the last couple circles.
- Grease a 12-count muffin tin. Take each pie crust circle and stretch it out slightly by hand, pressing around the circle, so it becomes slightly wider and fits at least ¾ of the way up the muffin tin cavity when pressed into it.
- In the large bowl with the watermelon rind, prepare the pie filling by combining it with the chopped strawberries, remaining sugar, lemon juice, and cornstarch. Stir well and set aside for now.
- Next, prepare your streusel topping. Combine the flour, brown sugar, granulated sugar, and melted butter in a medium bowl. Stir until well combined and crumbly.
- Use a slotted spoon to remove the filling mixture (letting the pink liquid that’s accumulated in the bowl remain in the bowl)* and add the filling to the mini crusts. Avoid overfilling.
- Spoon the streusel topping over each pie, pressing it down slightly with your fingers or the back of the spoon.
- Bake the mini pies at 425 degrees F for 20-23 minutes, or until the crust is cooked through and starting to turn a light golden brown color along the edges. Let cool in the pan for at least ten minutes, then remove by swirling a knife around the edge of each one and using a fork to help pop it out. Allow to continue cooling on a rack.
- Enjoy slightly warm! Store leftovers in the refrigerator for up to four days.
- You can drain the liquid from the filling mixture if it’s easier than using a slotted spoon; you want the fruit to stay juicy but avoid too much liquid in the filling (which will create a soggy crust).
- Place a baking sheet on the rack underneath the one your muffin tin on – that way just in case you overfilled the pies and the filling drips over the edge, it will land on your baking sheet instead of on the bottom of your oven.