Coat the bottom of a large saucepan with olive oil and place over medium heat. When oil is hot, add onion and sauté until softened, about 5 minutes. Add garlic, ginger, serrano pepper, garam masala, coriander, cumin, turmeric, and black pepper. Sauté 1 minute more.
Remove from heat and season with salt to taste. Adjust any other seasonings to your liking.