Best Oven-Roasted Ribs
["6 Tbsp. brown sugar", "6 Tbsp. paprika", "3 Tbsp. black pepper", "3 Tbsp. garlic powder", "1 1/2 tsp. salt", "9 Tbsp. (1/2 c.) Dijon or yellow mustard", "2 tsp. liquid smoke (optional)"]
["Preheat oven to 250\u00b0.", "Mix first 5 ingredients.", "Mix next 2 ingredients.", "Brush both sides of 4 slabs of baby-back ribs or 3 slabs of pork spare ribs with mustard then sprinkle with dry rub. Place on upper-middle oven rack.", "Place pan under ribs to catch drippings.", "Roast 2 to 3 hours for spare ribs, 1/2 to 2 hours for baby-back ribs."]
["brown sugar", "paprika", "black pepper", "garlic powder", "salt", "yellow mustard", "liquid smoke"]