Cut Beef Tenderloin (12 ounce) into thin julienne.
Cut up Red Chili Pepper (1), Orange Bell Pepper (1), and Onion (1). Combine with the beef.
Season with Pimiento Pepper (3 tablespoon), Garlic Paste (1 teaspoon), Ground Ginger (1/2 teaspoon), Soy Sauce (1/3 cup), Hoisin Sauce (1 tablespoon), Corn Starch (1/4 cup), Rice Wine (2 tablespoon), and Kosher Salt (to taste). Mix all ingredients well together and marinade at least one hour.
Heat Peanut Oil (1 cup), saute the beef and veggies at 375 degrees F (190 degrees C) until the onions are golden, remove with a slotted spoon, discard fat.
Add Chicken Stock (1/3 cup) and Spinach Leaves (12 ounce) to the pan, season with Kosher Salt (to taste) and simmer briefly then remove from heat.
Add the stir fried beef and veggies, add Toasted Sesame Oil (1 teaspoon), mix, check and adjust the seasoning. Serve by itself or over glass noodles, egg noodles or rice.