Preheat oven to 375 degrees F. Line a baking sheet with foil.
Mix sugar, coriander, cumin, salt, chile sauce and 1 teaspoon oil in a small bowl to form a smooth paste. Rub the paste over the pork.
Heat remaining 1 teaspoon oil in a large nonstick skillet over medium-high heat. Add the pork; cook, turning occasionally, until browned on all sides, about 3 minutes. Transfer to the baking sheet.
Roast the pork until just cooked through, 20 to 25 minutes (an instant-read thermometer inserted in the center should register 155 degrees F). Let stand, loosely covered with foil, for 5 minutes.
Meanwhile, make Sweet and Tangy Watermelon Salad. Carve the pork into 1/2-inch-thick slices. Serve with the watermelon salad.
Ingredient Note:Chile-garlic sauce, a blend of ground chiles, garlic and vinegar, is commonly used to add heat and flavor to Asian dishes. It can be found in the Asian section of large markets (sometimes labeled as chili-garlic sauce or paste) and keeps up to 1 year in the refrigerator.