Cook the bacon in a large skillet over medium-low heat until crisp but not too dark.
Transfer the bacon to a plate lined with paper towels, and reserve ¼ C of the rendered fat
When the bacon is cool, chop to make ½ C.
Bring the milk, ½ C water, the butter, and the reserved bacon fat to a simmer in a medium saucepan over medium heat.
Stir in the salt, onion powder, sugar, and cayenne
Add the flour and, using a wooden spoon, stir very quickly in one direction. The flour will quickly absorb the liquid and form a dough.
Continue stirring to cook the flour (and remove its "raw" taste) and simmer off more of the moisture until the dough pulls away from the sides of the saucepan, an additional minute or two.
Step 2
Transfer the dough to the bowl of an electric mixer fitted with the paddle attachment.
Add the eggs one at a time, mixing on medium speed until each is incorporated into the dough, which will change from shiny to sticky as the eggs are worked in.
On low speed, stir in 1 C of the Parmesan and the bacon until just combined.
Using a small ice cream scoop (about 2" in diameter), scoop the dough onto the prepared baking sheets
Top the gougères with an equal amount of the remaining ¼ C Parmesan.
Bake until puffed and golden, 20-25 minutes. Serve warm.