Hot and Sour Thai Soup

Build the broth. In a medium or large pot, combine broth, lemongrass, garlic, ginger, and makrut lime leaves (if using). For the best lemongrass flavor, give the lower stalk a good bruise with the side of your knife, and if you want to get extra nerdy, split thicker pieces lengthwise. Bring to a simmer over medium-high heat, then reduce to medium and simmer for 10 minutes to infuse.

Make serving easier (optional but smart). If you used big pieces of lemongrass, ginger, or makrut leaves, fish them out now. They did their job, and it is nicer to serve the soup without surprise chewy bits.

Add the vegetables. Add mushrooms, sliced chiles (if using), and tomato wedges. Simmer until mushrooms are tender, about 5 minutes.

Cook the shrimp. Add shrimp and cook just until pink and firm, 2 to 3 minutes.

If using chicken, add thin slices and simmer until cooked through, about 5 to 7 minutes depending on thickness (target 165°F / 74°C).

If using tofu, use firm or extra-firm, cube it, and add it now to warm through for 1 to 2 minutes. If you want more texture, pan-sear the cubes first and then add them to the bowls.

Season like a pro. Turn heat to low. Broth and fish sauce salinity varies, so start by stirring in 1 1/2 tablespoons fish sauce, then add more to taste. Stir in chili paste, sugar, and start with 2 tablespoons lime juice. Keeping the heat low helps the lime stay bright.

Optional coconut move. If using coconut milk, stir it in now for a creamy finish.

Taste and dial it in. This is the whole point. Add more lime for brightness, more fish sauce for savory depth, more chili paste for heat, or a pinch more sugar if it tastes too sharp.

Finish and serve. Ladle into bowls and top with cilantro and scallions. Serve with extra lime wedges. If you want it more filling, spoon the soup over cooked rice or add rice noodles right into the bowl.