Preheat oven to 375 and grease a 9x13 pan with butter or pan spray. Place the pretzels in a food processor and process in pulses until they are broken down into small pieces but not completely pulverized.
Mix the pretzels, butter and sugar together well and spread into the bottom of the pan. Bake for 10 minutes, then cool completely.
In the bowl of a stand mixer, whip the cream cheese with sugar and vanilla using the paddle attachment until smooth and creamy, scraping down the bowl as needed. Transfer to another bowl. Then whip the cream using the whisk until stiff peaks form.
Carefully fold the whipped cream into the cream cheese mixture until smooth, taking care not to deflate the cream. Spread over the pretzel crust, making sure the mixture goes all the way to the edges of the pan so that no jello can leak down into the crust. That way the crust stays crisp.
Add the jello mix to a bowl that is heat safe and add the boiling water. Stir well. Place in the fridge for about an hour until it has the consistency of egg whites. Add the strawberries and pour over the filling. Place in the fridge for 2-4 hours, then serve. Store in the fridge.