Combine squash, fermented salty shrimp, green chili pepper, and green onion in a bowl. Mix well. Set aside. Cut the beef into thin 2 inch long strips along the grain. Put them into a bowl. Add the soy sauce, ground black pepper, sesame oil, and potato starch. Mix well by hand.
Heat up a non-stick skillet with 1 tablespoon oil over high heat. Swirl the skillet to let the oil coat evenly. Add the marinated beef and spread it evenly with a spatula. Let it cook for 1 to 2 minutes until it turns a little brown and crispy on the bottom. Turn it over with the spatula. Cook another 1 to 2 minutes until no longer pink and slightly crunchy. Remove from the heat. Set it aside.
Heat up a large frying pan and add 2 tablespoons cooking oil. Add garlic and onion and cook for a couple of minutes until fragrant and the garlic turns a little brown. Add the mixture of squash and stir for 1 minute. Reduce the heat to medium and cook for about 4 to 5 minutes, stirring occasionally until the squash softens but is still a little crispy. Remove from the heat. Add the cooked beef and toss with the spatula until well mixed.
Put some onto rice on a bowl. Add the squash and beef over top. Serve by itself or with kimchi and other side dishes.
