In a small bowl, whisk together the salt, smoked paprika, brown sugar, chili powder, black pepper, garlic powder, onion powder, and ground cumin until well combined and no lumps remain. In a separate bowl, whisk together the ketchup, brown sugar, cider vinegar, espresso, yellow mustard, and soy sauce until smooth and fully incorporated. Set both mixtures aside—the dry rub will be applied to the ribs shortly, and the sauce will be used for finishing after pressure cooking.

Remove the silver skin (thin membrane) from the back of the ribs by sliding a knife under it and pulling it away—this allows the seasoning and smoke flavor to penetrate the meat. Cut the slab into 3-4 bone sections to fit comfortably in your Instant Pot. Generously rub the dry spice mixture from Step 1 all over each section, making sure to coat all sides evenly. I find it helpful to use my hands to really work the spices into the meat and create an even crust that will develop flavor during pressure cooking.

Pour the water and liquid smoke into the Instant Pot and stir to combine. Arrange the seasoned rib sections on the trivet or steamer rack, stacking them bone-side down if necessary to fit. Seal the lid, set the valve to 'sealing,' and cook on high pressure for 30 minutes. The liquid smoke combined with the pressure will infuse the meat with deep, smoky flavor while the high heat breaks down the collagen and makes the ribs tender.

Once the cooking time is complete, allow the pressure to release naturally for 15 minutes—this gradual depressurization keeps the meat tender and juicy. After 15 minutes, carefully release any remaining pressure by opening the valve. Remove the ribs with tongs and arrange them bone-side down on a broiler-safe pan or sheet. Pat the ribs dry with paper towels to help them brown better under the broiler.

Brush the ribs generously with the sauce mixture from Step 1, coating the meat side evenly. Place the pan under a preheated broiler set to high and broil for 5 minutes, watching carefully to prevent burning. The sauce will caramelize and the edges will char slightly, creating a beautiful, flavorful crust. Remove the pan from the broiler, brush with an additional layer of sauce, and serve immediately while still hot. I like to serve with extra sauce on the side for dipping—the spiced ketchup base really complements the smoky, tender meat.