Heat a large saucepot over medium-high heat.
Add the bacon and cook until crispy, stirring often, about 5 to 7 minutes.
Remove the bacon to a paper towel-lined plate to drain.
Discard all but 2 tablespoons of the bacon grease.
To the hot grease, add the garlic. Cook for 1-2 minutes, stirring constantly, until fragrant.
In a small bowl stir together the flour and dry ground mustard. Add the flour to the pot and stir to combine. Cook for 1 minute.
Pour in the beer and stir. Cook for 2 minutes.
Add the cream cheese and cook until melted, stirring often to help break down the cheese.
Add the cheddar and Colby-jack cheeses. Stir to combine until the cheeses have melted and the sauce is thick and smooth, about 5-8 minutes.
Season with salt and pepper to taste. Add the hot sauce and stir to combine.
Add almost all of the bacon into the dip, saving a little for garnish. Stir to incorporate the bacon.
Transfer to a serving bowl (or a crock pot set on warm), sprinkle the reserved bacon on top. Serve immediately with soft or hard pretzels.