Wash 2 lbs. of small red potatoes thoroughly. Place in a large pot, cover with water, add 1 tsp. of salt, and bring to a boil. Cook for 12-15 minutes until tender. Drain and cool slightly before slicing into ¼-inch thick half-moons.

Heat a skillet over medium heat and add 4 oz. of bacon. Cook until crispy, about 6-8 minutes. Remove bacon and set aside, leaving bacon fat in the skillet.

In the same skillet, add 1 diced yellow onion. Cook over medium heat until soft and translucent, about 5 minutes.

Lower the heat and stir in 1 tbsp. of stone ground mustard. Add 1 tbsp. of sugar, ½ tsp. of salt, ¼ tsp. of freshly cracked black pepper, and ⅓ cup of apple cider vinegar. Whisk until fully combined.

Add the sliced potatoes and chopped bacon into the skillet with the dressing. Gently toss until the potatoes are well-coated.

Serve warm immediately or chill for an hour before serving cold.