Clean and cut the squid and tofu into bite-sized pieces.
Julienne the onion, green onion, and red chili pepper.
Add cooking oil to a pan and sauté minced garlic until fragrant.
Add the squid and stir-fry quickly over high heat.
Add the tofu and mix lightly.
Add the onion, green onion, and red chili pepper, and continue stir-frying.
Season with soy sauce, red chili powder, sugar, sesame oil, and black pepper.
Mix everything well, stir-fry, and finish.