In a medium bowl, combine graham cracker crumbs, coarsely chopped pretzels, chopped pecans, and granulated sugar. Pour in melted unsalted butter, and mix thoroughly until the ingredients are evenly coated. Press this mixture firmly into the bottom and up the sides of a greased 9-inch springform pan. Chill in the refrigerator for at least 30 minutes to set.

While the crust firms up, take 1.5 cups of fresh strawberries and puree them in a blender or food processor until smooth. Carefully add boiling water, sugar, and cornstarch to the strawberry puree, blending until everything is well incorporated.

Transfer the blended strawberry filling to a saucepan and place it over medium heat. Continuously stir as the mixture heats up, bringing it to a gentle boil. Keep stirring for about 3 minutes, until the filling thickens and becomes glossy.

Once thickened, remove from heat and stir in vanilla extract. Allow the mixture to cool slightly before folding in sliced strawberries.

Carefully pour the strawberry filling into the chilled crust, spreading it evenly, and arrange sliced strawberries over the top. Cover the pie with plastic wrap and chill in the refrigerator for at least 2 hours.

When ready to serve, gently remove the outer ring of the springform pan. Slice the pie into portions, and serve with a dollop of whipped cream.