Step 1: Create the BBQ Bourbon Glaze
In a medium saucepan, combine the bourbon, barbecue sauce, brown sugar, soy sauce, apple cider vinegar, minced garlic, Dijon mustard, onion powder, and cayenne (if using). Bring to a simmer over medium heat, stirring to dissolve the sugar. Reduce heat to medium-low and let it simmer gently for 15-20 minutes, stirring occasionally, until the mixture has reduced by about a third and thickened to a glaze consistency that will coat the back of a spoon. Remove from heat and let cool slightly. Reserve about ½ cup of the glaze in a separate bowl for serving.

Step 2: Marinate the Steak
Place the cubed steak in a large bowl or resealable plastic bag. Add the olive oil, salt, black pepper, and smoked paprika. Toss to coat evenly. Pour in about ¾ of the warm glaze (reserving the rest for later use). Toss the steak until every piece is thoroughly coated. Cover or seal and marinate at room temperature for 30 minutes, or in the refrigerator for up to 2 hours. If refrigerated, let sit at room temperature for 15 minutes before cooking.

Step 3: Sear the Steak Bites
Heat a large cast-iron or heavy-bottomed skillet over medium-high heat until very hot. Add the high-smoke-point oil. Using tongs, remove the steak bites from the marinade, letting excess drip off (discard the used marinade). Working in batches to avoid overcrowding, add the steak bites in a single layer. Sear undisturbed for 2-3 minutes to develop a deep brown crust. Flip and sear the other sides for another 2-3 minutes for medium-rare, or to your desired doneness. Transfer the seared steak bites to a clean plate. Repeat with remaining batches.

Step 4: Deglaze and Build the Final Sauce
Reduce the heat to medium. Add the butter to the empty skillet. Once melted, pour in the remaining reserved (unused) glaze from Step 1. Use a wooden spoon to scrape up all the flavorful browned bits (fond) from the bottom of the pan. Let the sauce simmer for 1-2 minutes to thicken slightly and combine with the fond.

Step 5: Glaze the Steak Bites
Return all the seared steak bites and any accumulated juices on the plate back to the skillet. Toss vigorously for 1-2 minutes, until the steak is reheated and every piece is generously and gleamingly coated in the thick, glossy BBQ bourbon glaze.

Step 6: Garnish and Serve
Remove from heat. Transfer the glazed steak bites to a serving platter. Drizzle with some of the reserved ½ cup of clean glaze for extra sheen and flavor. Garnish generously with sliced green onions or fresh parsley. For a final touch, sprinkle with a pinch of flaky sea salt to enhance all the flavors.

Step 7: Serve Immediately
Serve the steak bites hot, with toothpicks for easy grabbing as an appetizer. If serving as a main course, they are fantastic over creamy mashed potatoes, cheesy grits, or with a simple side salad. Provide extra glaze on the side for dipping