Preheat oven to 350℉. Bring two cups of water to a boil. In a large bowl combine boiling water and Jell-O. Stir until completely dissolved. Set aside to cool to room temp while you prep the rest of the dish.
Place 3 cups of pretzels in a Ziploc bag and use a rolling pin to crush into tiny pieces.
In a medium saucepan, melt 8 tbsp of butter. Once melted, add ¼ cup of white sugar and stir. Gently mix in crushed pretzels. Once combined, transfer to a 13 x 9 glass casserole dish, pressing the pretzel mixture down evenly.
Bake for 10 minutes, then cool to room temp.
Beat 8 oz of softened cream cheese and ½ cup of sugar for several minutes until fluffy and evenly combined. Fold in 8 oz of Cool Whip until there are no remaining streaks of cream cheese.
Spread the mixture over the cooled pretzels, evenly spreading to the edges to create a tight seal. (You don't want the Jell-O to seep down to the bottom layer). Cover with plastic wrap and refrigerate for 30 minutes.
Stir sliced strawberries into your room temperature Jell-O. Pour the strawberry Jell-O mixture evenly over your cooled cream cheese layer. Cover with plastic wrap and refrigerate until Jell-O is set, about 3 - 4 hours.