Light your grill or smoker and bring the temperature up to 225°F.
Lightly coat the skin of the brats in olive oil to keep them from drying out and splitting while cooking.
Once the grill or smoker is at 225°F. Add your smoking wood. this can be a wood chunk added to the hot charcoals, or wood chips added to smoker box. Close the lid, limit the oxygen consumption into the smoker and keep the temperature around 225°F.
Once smoke is actively being produced, put your bratwursts on the grill or smoker, AWAY from the heat source so that they are being cooked INDIRECTLY. Close the lid and continue to maintain the temperature.
Once the brats have reached 165°F internally using an instant read thermometer, you can remove them from the grill, likely after about 60 minutes.
If you wish to have a crispier exterior, you can throw the brats on a hot grill for 1-2 minutes per side just before they reach 165°F to finish them without overcooking.
Serve on a bun with the braised onions, sauerkraut, or other condiments.