I've only made turkey Brats (available at Whole Foods) for many many years now. If I'm grilling them outside, I just grill them over indirect heat for about 10 minutes, turning occasionally, & then move them over direct heat for another 10 minutes, turning occasionally until brown.
If I'm doing them inside, I simmer them in water, chicken stock, or beer for around 10 minutes, again turning, & after the liquid cooks off, I add some extra-virgin olive oil to the pan & continue sauteing until they're browned & cooked through.
I used to brown them first & then simmer, but found that the simmering removed all of the attributes of the browning.