For the pretzel crust: Preheat the oven to 350 degrees F.
Crush the pretzels in a large resealable plastic bag with a rolling pin. Mix in a bowl with the butter and brown sugar. Press into a pie pan and bake for 8 minutes. Remove and set aside to cool.
For the strawberry filling: Put 1 1/2 cups water, the granulated sugar, cornstarch and gelatin powder in a saucepan. Stir together and bring to a boil. Cook until it starts to thicken, then remove from the heat.
Put the strawberries in a bowl and pour over the sauce, gently tossing together. Allow to cool slightly, then carefully pile the coated strawberries into the cooled pie crust. Spoon over any leftover sauce and refrigerate, uncovered, for 4 hours.
Pour the cream into the bowl of a mixer, and use the whisk attachment to whisk until billowy. Top the pie with a huge layer of whipped cream, spooned on with a big spoon.