Step 1 In a medium bowl, toss the graham crumbs, milk powder, sugar and salt with your hands in a medium bowl to evenly distribute the dry ingredients.
Step 2 In a small bowl, whisk the butter and heavy cream together. Add to the dry ingredients and toss again to evenly distribute. The butter will act as a 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 add it to the mixture.
Step 3This makes slightly more crust than is needed for the remainder of the recipe. Eat immediately, or deploy as directed in the recipe. The crust is easiest to mold just after mixing. Stored in an airtight container, graham crust will keep fresh for 1 week at room temperature or for 1 month in the fridge or freezer.