Heat olive oil in a heavy-bottomed pan over medium-high heat. Add beef chuck cut into bite-sized pieces and sear for 4–5 minutes until browned. Transfer to a plate and set aside.

In the same pan, add bruised lemongrass (if using), diced brown onion, minced ginger, and minced garlic. Sauté for 2–3 minutes until the onion is translucent.

Stir in yellow curry paste for about 30 seconds. Pour in coconut milk, brown sugar, and fish sauce. Return the browned beef and bring to a simmer.

Reduce heat to low, cover the pot, and let simmer for 2 hours.

After 2 hours, remove lid and increase heat to medium-high. Simmer uncovered for 15 minutes until sauce thickens.

Serve hot with jasmine rice, topped with crushed peanuts, lime wedges, Thai basil, and sliced bird’s eye chili.