Line a small 4×5 loaf pan (I only had a full size pan handy) with plastic wrap, letting the excess hang over the sides.

In a small bowl, combine the water and gelatin. Stir. Let sit for 5 minutes.

Combine cheese, milk powder, salt, and tartar in the bowl of a food processor, pulsing a few times to combine.

Heat milk in a small saucepan over medium heat.

When milk begins to simmer, remove from heat, transfer hot milk to a measuring cup (to make pouring easier) and slowly add milk into the food processor feed tube.

As you slowly add the milk, pulse the food processor.

Add prepared gelatin.

Turn the food processor on, and continue to stir until the mixture becomes perfectly smooth. Scrap the sides if needed and whir again.

Working quickly, transfer the mixture into the prepared mold, pressing the mixture down into the pan with a spatula to help eliminate any air bubbles.

Smooth surface of cheese, and cover with the overlapping plastic.

Chill in the refrigerator for at least 3 hours, or overnight. (If pressed for time, a little over an hour and a half in the freezer will work too!)

Slice, cube, or melt as needed and use as you would Velveeta or individually wrapped processed American cheese.