Make the yum yum sauce. Add all the ingredients to a small blender and blend until smooth. Taste, adjust as needed, and set aside.
Pat steak dry, cut into chunks and add to a bowl. Add the vinegar, ½ tb sesame oil, soy sauce, ground ginger, onion powder, S&P. Toss to coat well. Marinate at least 30 min or up to 4 hours for maximum flavor (or skip it all together).
Heat a large cast iron skillet over medium high heat. Add 2 tb of the butter and 1 tb sesame oil. Once melted, add the veggies and sauté 10-12 minutes until the veggies have softened. Sprinkle with salt and pepper. Transfer to a plate.
Add remaining butter and sesame oil to the pan. Add the beef in a single layer, working in batches. Do NOT overcrowd the pan or meat will come out tough.
Toss the beef but do NOT cook longer than 3-4 minutes max!
Remove pan from heat. Toss w bbq sauce and plate meal immediately so the beef doesn’t cook longer in the pan—cooked rice, veggies, beef and top with yum yum sauce and sesame seeds. Enjoy!
