Season the meat with salt, pepper and herbs inside and out. Roll the leg up tightly and tie with kitchen twine to ensure even cooking. Let it sit uncovered in the fridge overnight. I’ve found about 2 teaspoons of kosher salt for a 3-4 lb goat leg is great.
The next day, 1.5 hours before you want to serve (assuming a 3-4 lb leg) preheat the oven to 250 °F and place the leg in the oven. Set a timer for 1 hour, and take the temperature in the middle of the roast with the thermometer. When the internal temperature comes up to your target temperature, remove the leg from the oven and allow to cool on its rack in a warm-ish location for 15-20 minutes. You could even turn the oven off and let the roast rest in there with the door slightly ajar.
Meanwhile, heat up your sides and garnishes and prepare to serve.
Finally, heat a few tablespoons of oil in the sauté or cast iron pan on high. Turn on the hood, and or open a window, since you’ll be using some high heat for a few minutes. When the oil is just starting to smoke gently, reduce the heat to medium-high and brown the roast deeply on all sides.
After the roast is browned, transfer to a cutting board, remove the twine, cut into slices with a sharp knife and serve immediately.