Sambal oelek is made by the same guy who brought you sriracha sauce. It's a thick chunky-style paste, but not quite as hot as sriracha. But if your idea of hot is two turns of the pepper mill, then stick with just 1 teaspoon of the stuff.
I found the original recipe at Cooking Light. It called for thinly sliced steak, but I tried ground beef and it works even better, because dumping excess grease is faster than thinly slicing. I also substituted balsamic vinegar for the sherry, which I never have on hand and didn't feel like buying a whole bottle just for 2 teaspoons full of it. Finally, although I have also used Japanese buckwheat soba noodles and no one complained too much, I usually take the easy way out and make rice.
2 Tablespoons soy sauce (regular or low-sodium)
1 tsp. sugar
1/2 Tablespoon cornstarch
2 teaspoons balsamic vinegar
1 Tablespoon hoisin sauce
1 Tablespoon rice vinegar (or 2 tsp. cider vinegar)
1 teaspoon sambal oelek (chile paste with garlic), or more to taste
2 teaspoons vegetable oil
1 Tablespoon minced fresh ginger
2 cloves garlic, minced
1 lb. ground beef, preferably 90% or more (any less and there will be too much grease to pour off)
1 bunch of scallions, cut on the diagonal in 2-inch segments
Hot cooked rice, in whatever quantity serves 4 in your house
1 Tablespoon sesame seeds, for garnish (optional)
Combine the first 7 ingredients in a small bowl and set aside.
Heat a large skillet over a medium-high flame until hot. Add the oil, wait 10 seconds to heat, then add ginger and garlic. Stir constantly for 30 seconds.
Add beef. Stir, breaking up clumps as you go, until the meat is browned. Carefully pour off excess grease, then return skillet to the burner.
Add sauce, and stir continuously for one minute or until thickened. Mix in scallions, then cover and turn off heat while you wait for the rice to finish cooking because you didn't believe it would cook that fast.
Plate the rice, top with beef and sprinkle with sesame seed, if desired, then serve.