Prep: Slice 2 pounds russet potatoes into fries, transferring to a bowl of tepid water as you go. Heat 2 inches of peanut or vegetable oil, shortening, lard, or a combination of fats in a deep wide pot over medium heat until a deep-fry thermometer registers 375 degrees F. Drain the potatoes and dry well.
Fry: Add half of the potatoes to the pot and fry, stirring gently, until they soften and blister, 3 to 4 minutes (do not let them color). Remove with a slotted spoon or skimmer to a paper towel-lined baking sheet. Repeat with the remaining potatoes. Transfer to the freezer until firm, at least 1 hour.
Refry: When ready to serve, reheat the oil to 375 degrees F over medium-high heat. Working in 4 small batches so the oil stays hot, fry the potatoes until golden brown, about 5 minutes. Transfer to fresh paper towels to drain. Season with salt.
Strip the leaves from a few rosemary and thyme sprigs. Pulse in a food processor until fine, then toss with coarse salt.
Pulse 3 slices cooked bacon in a food processor until fine; toss with 3 tablespoons coarse salt.
Mix equal parts paprika, grated parmesan and coarse salt.
Stir 1/2 to 1 minced chipotle pepper in adobo sauce into 1/2 cup ketchup. Add a splash of balsamic vinegar.
Add a little Sriracha sauce (or other hot sauce) to 1/2 cup mayonnaise. Mix in the zest and juice of 1 lime.
Mix 1/2 cup dijon mustard, a spoonful of horseradish and some chopped parsley.