1. Divide the onion into equal quarters, then slice the onion quarters.
2. Preheat a large, heavy-bottomed skillet (ideally a cast-iron type skillet). Pour in the oil. Sear the brats for about 3 minutes on medium-high heat, then flip them with tongs. Allow the other side of the brats to cook for another 3 minutes.
3. Between the sausages, add the onions and let them cook for about 2 minutes. Make sure to stir occasionally until they turn golden.
4. Repeat the flipping process for the sausages, add in the beer, cover the mixture, and let it cook for about 10 minutes on low heat, flipping halfway through. The temperature at this point should be 71 degrees Celsius/160 degrees Fahrenheit on the inside of the sausages. If you don’t have a meat thermometer, split one sausage in half and check to see if it’s done.
5. Take the brats off the heat, then season to taste with salt and pepper, and simmer the sauce for 2 minutes. Bring the sausages back to the pan and combine them with the sauce.
6. Serve right away.

This recipe can be made within an entire duration of 25 minutes, including a prep time of 5 minutes and a cook time of 20 minutes. Feel free to try it at home, but if you still want more recipe ideas, then this video recipe might interest you.