Preheat your oven to 400°F (200°C) conventional (see note 1 if using a convection oven) and begin preparing the Jell-O layer (Jelly). In a heatproof bowl, combine the strawberry Jell-O powder with boiling water and stir until completely dissolved. Set aside to cool to room temperature (see note 2).
Place the pretzels into a food processor and pulse until broken into small pieces. Avoid over-processing. You want a mix of small chunks and some fine crumbs (see video for visual).
Transfer the crushed pretzels to a bowl, add the melted butter and sugar, and mix until evenly coated.
Transfer the mixture to a 9×13-inch baking dish and press firmly into an even layer. Bake for 8–10 minutes, then remove from the oven and allow to cool completely to room temperature (about an hour).
Once cool, begin the cream layer. In a large bowl, add cream cheese and sugar and using a hand or stand mixer on medium-high speed, whip until light and fluffy.
Add the whipped topping and gently fold using a spatula until fully combined and no streaks remain. Do not overmix.
Spread the cream mixture evenly over the cooled pretzel layer, making sure to spread it all the way to the edges to create a tight seal (see note 3). Refrigerate for 30 minutes to allow the layer to firm up.
Hull and slice the fresh strawberries and arrange them evenly over the chilled cream layer.
Carefully pour the cooled Jell-O evenly over the strawberries.
Refrigerate for 3–4 hours, or until the Jell-O is fully set. Slice and serve.