Prepare the Crust:
Preheat oven to 350°F (175°C).
In a mixing bowl, combine crushed pretzels, melted butter, and sugar.
Press the mixture firmly into the bottom of a 9x13-inch baking dish.
Bake for 10 minutes, then cool completely.
Make the Cream Cheese Layer:
In a large bowl, beat softened cream cheese and sugar until smooth.
Fold in whipped topping until fully combined.
Spread evenly over the cooled crust, sealing edges to prevent Jell-O from seeping through. Refrigerate while you prepare the topping.
Prepare the Strawberry Layer:
In a medium bowl, dissolve strawberry gelatin in boiling water. Stir until completely dissolved.
Add cold water, mix, then allow to cool to room temperature (do not let it set).
Stir in sliced strawberries.
Assemble:
Pour the strawberry mixture gently over the cream cheese layer.
Refrigerate for at least 4 hours, or until the gelatin is fully set.
Serve:
Slice into squares and serve chilled.