1. In a large bowl, toss the beef slices with curry powder, salt, and pepper. Let it marinate for at least 15 minutes to allow the flavors to meld.
2. Heat olive oil and butter in a large skillet over medium-high heat. Add the beef and cook until browned, about 4-5 minutes. Remove the beef from the skillet and set aside.
3. In the same skillet, add mushrooms and sauté until they’re golden and have released their moisture, about 5 minutes.
4. Reduce the heat to medium and add coconut milk, peanut butter, soy sauce, lime juice, ginger, and garlic to the skillet. Stir until the peanut butter is fully incorporated, creating a smooth sauce.
5. Return the beef to the skillet and simmer everything together for an additional 5 minutes, allowing the sauce to thicken slightly.
6. Meanwhile, prepare the mango salsa by combining diced mango, red onion, cilantro, jalapeño, and lime juice in a bowl. Mix well and set aside.
7. Serve the curried beef and mushrooms hot, topped with a generous spoonful of mango salsa.

Cooking this dish brings back memories of my abuela teaching me to trust my senses in the kitchen. Listen to the sizzle, watch the sauce thicken, and taste as you go. Each step is an opportunity to connect with the food and make it your own.