Preheat oven to 350 degrees F (175 degrees C).

Place pretzel twists in a large plastic freezer bag with a zipper or sealable top. Using a rolling pin, crush pretzels to small pieces. You can also take a large flat object, place it over the bag, and press down to crust the pretzels.

Melt coconut oil in a saucepan or in the microwave. Stir in 1/2 tablespoon of agave and pretzel pieces. You want to make sure that all the pretzel pieces are covered in coconut oil. Add another 1/2 tablespoon of coconut oil, if necessary.

Press coated pretzel pieces into a 10-inch tart pan. Use a metal spoon to help guide pretzels into the curves of your tart pan. Place tart pan on a baking sheet and bake for 8 to 10 minutes, or until the pretzels have browned a little. I baked it for 10 minutes. Remove crust from oven and set aside.

Heat milk in a saucepan over medium heat until it starts to bubble slowly. Add chocolate and reduce heat to medium low. Stir until chocolate is well incorporated. Mix in 2 tablespoons of agave. Pour chocolate mix into tart pan. Let tart sit in room temperature for an hour. Refrigerate tart, uncovered, for at least 3 hours before serving. The longer you let it chill, the easier it will be to slice. Don't wrap the tart in plastic wrap or foil before popping it in the refrigerator because you'll run the risk of having the wrap stick to the top of the tart.

Top with coconut, salt, or additional pretzel pieces if you like. Serve chilled. Store in a sealed container for up to 2 days. The filling will be fine for longer, but the pretzels will surely be soggy if you keep this for more than 2 days.