Add all beef ingredients except flank steak to a food processor and blend until smooth. Set aside.
Set Instant Pot to saute/hot. Once hot, add some sesame oil and sear flank steak on all sides. Remove from heat, then add pear mixture to Instant pot. Layer seared flank steak on top of pear mixture and spoon pear mixture over top.
Set Instant Pot to high/manual for 20 minutes followed by natural release. You can also use a slow cooker on low for 6-8 hours.
Once cooked, remove flank steak and allow to rest on cutting board for 5 minutes. Slice against the grain.
Meanwhile, whisk together Greek yogurt and gochujang. Set aside.
Arrange bowls with rice, lettuce, and kimchi. Add sliced flank steak, gochujang "mayo," cilantro, jalapeños, and sesame seeds before serving.