Step 1 In a medium bowl, toss together the graham cracker crumbs, milk powder, sugar and salt with your hands to evenly distribute.
Step 2 In a separate bowl, whisk together the melted butter and heavy cream. Add to the dry ingredients and toss again to evenly distribute. The butter will act as glue, adhering to the dry ingredients and turning the mixture into a bunch of small clusters. The mixture should hold its shape if squeezed tightly in the palm of your hand. If it is not moist enough to do so, melt an additional 1 to 1 1/2 tablespoons butter and mix it in with the crust base.
Step 3This makes about 2 cups crust base, more than is needed for the remainder of the recipe. Eat the base, or use as desired in other recipes. Store in an airtight container for up to one week at room temperature, or for one month in the refrigerator or freezer.