Steps
1. In a small bowl, mix the brewed coffee with instant coffee powder until dissolved.
2. Marinate the beef strips in half of the coffee mixture, soy sauce, salt, and pepper for 10 minutes.
3. Heat olive oil in a pan over medium-high heat.
4. Add garlic and onion, sauté until fragrant.
5. Add marinated beef and stir-fry for 3-4 minutes until browned.
6. Add bell pepper and remaining coffee mixture, cook for another 2-3 minutes until vegetables are tender and sauce slightly reduces.
7. Adjust seasoning with salt and pepper.
8. Garnish with fresh cilantro and serve hot.