Warm a large saute pan or cast iron skillet over medium-high heat to preheat for 3-4 minutes until blazing hot but not smoking. Meanwhile, liberally dry short ribs with paper towels and generously season all over with salt and pepper.
When pan is ready, add olive oil to the pan and immediately transfer short ribs over, in an even layer, to brown on the first side. Let brown, undisturbed, 3-4 minutes per side. Turn heat to medium if pan is getting too hot. Repeat process until all ribs are browned and transfer to a slow cooker pot.
Next, make your Asian marinade. In a high-speed blender, combine all marinade ingredients and blend until very smooth. Pour marinade over ribs, submerging completely. Add lid to slow cooker pot and transfer to refrigerator to chill and marinate overnight, at least 8-12 hours.
After marinating, return short ribs to slow cooker machine and cook on low for 8 hours until ribs are fork tender and start to fall off the bone.
Transfer ribs to a sheet pan or serving platter. With tongs and a fork, gently scrape off any excess fat or gristle on exterior. Set aside and tent pan with foil to keep ribs warm.
With a ladle, begin removing fat and impurities from the top of your short rib sauce. All of the liquid gold is under the top fat layer. When finished, pour sauce into a medium saucepan and bring to a simmer.
When sauce is simmering, slowly whisk in arrowroot, a little at a time, making sure to whisk continuously to prevent any lumps. Let simmer for 4-5 minutes, whisking continuously, until thickened.
Ladle some sauce atop each short rib then garnish platter with fresh lime wedges, sliced scallions and toasted white sesame seeds, for serving.