Coney Island Hot Dogs

Name: Coney Island Hot Dogs
Ingredients: 2 Tbsp. extra-virgin olive oil; 4 garlic cloves, finely chopped; 1 medium white onion, finely chopped, plus more for serving; 1¼ tsp. Diamond Crystal or ¾ tsp. Morton kosher salt, divided; 2 Tbsp. unsalted butter; 2 tsp. chipotle chile powder; 1½ tsp. ground cumin; ½ tsp. ground coriander; Pinch of cayenne pepper; Freshly ground pepper; 2 Tbsp. double-concentrated tomato paste; 1 Tbsp. miso; 1 Tbsp. balsamic vinegar; 1 lb. ground beef; 1 tsp. sugar; 1 Tbsp. all-purpose flour; 8 hot dogs; 8 hot dog buns; Yellow mustard (for serving)