Preheat the oven to 400 degrees F.

Place the water, milk, butter, and salt in a medium saucepan and bring to a simmer.

Stir in the flour, over medium heat. Continue to stir until well combined and pulling away from the sides of the pot and into a ball.

Place the dough in a mixing bowl and let cool for about a minute. Beat in the eggs, one at a time.

Add the garlic powder, dry mustard, and cheese, and stir to combine.

Pipe into 2 inch mounds, onto parchment-lined baking sheets. Top with more cheese, and bake for 25 minutes, or until puffed and golden.