Preheat your oven to 350°F (175°C). Lightly grease a 9x13-inch pan with butter or nonstick cooking spray to help the pretzel crust release cleanly when sliced.

Place the pretzels in a large zip-top bag and crush them with a rolling pin or the bottom of a heavy pan. Aim for small, uneven pieces rather than fine crumbs for the best crunchy texture.

In a medium bowl, combine the crushed pretzels, 3 tablespoons granulated sugar, and melted butter. Stir until all the pretzels are evenly coated and glossy.

Pour the pretzel mixture into the prepared pan. Press it firmly and evenly into the bottom using the back of a spoon or the bottom of a measuring cup. Bake for 8–10 minutes, until fragrant and lightly golden at the edges. Cool completely on a wire rack before adding the next layer.

In a large bowl, beat the softened cream cheese with powdered sugar and vanilla using a hand or stand mixer until smooth and fluffy, about 2–3 minutes. Scrape down the sides of the bowl as needed to avoid lumps.

Gently fold the whipped topping into the cream cheese mixture with a spatula until creamy and smooth, taking care not to deflate the mixture.

Once the pretzel crust is completely cool, dollop the cream cheese mixture over the crust. Very gently spread it all the way to the edges to form a complete seal over the pretzels. This barrier keeps the Jell-O from soaking into the crust.

Cover the pan and refrigerate for at least 30 minutes so the cream cheese layer firms up while you prepare the gelatin.

Add the strawberry gelatin powder to a large heatproof bowl. Pour in 2 cups of boiling water and stir for a full 2 minutes, until the gelatin is completely dissolved.

Stir in 1 1/2 to 2 cups of cold water (use 1 1/2 cups for a firmer set). Let the mixture sit at room temperature until it cools and thickens slightly to a syrup-like consistency, about 20–30 minutes. Do not pour it over the cream cheese layer while still hot or very thin.

Gently stir the sliced strawberries into the cooled, slightly thickened gelatin until the fruit is evenly coated.

Remove the chilled pan from the refrigerator. Slowly spoon the strawberry gelatin mixture over the cream cheese layer, rather than pouring it all at once, to keep the layers distinct.

Return the pan to the refrigerator and chill for at least 4 hours, or overnight, until the gelatin is fully set—jiggly but not liquid. Longer chilling gives cleaner slices.

Cut into squares with a sharp knife, wiping the blade between cuts for neat layers. Top each serving with a dollop of whipped topping and garnish with fresh mint or extra strawberry slices if desired.