Adjust oven racks to the upper and lower-middle positions and heat oven to 375 degrees Fahrenheit.
Line 2 large baking sheets with parchment paper.
Chop uncooked bacon into 1/8 size pieces. Cook until crisp. Cool on paper towels to absorb grease.
Whisk the flour, dry mustard, and salt together in a medium bowl; set aside.
In the bowl of an electric mixer, combine cheese and butter until thoroughly blended.
Add the dry ingredients and bacon and beat at low speed until dough is no longer crumbly.
Roll dough into ½ ounce balls.
Bake until lightly brown, about 16-18 minutes, rotating the baking sheets front to back and top to bottom halfway through the baking time.
Remove from oven.
Cool the cookies on the sheets for 5 minutes at room temperature, then remove to wire racks to cool completely.