Here’s a great Mexican chorizo recipe that you can adapt with cayenne to vary the heat level to your liking.
(note, that’s red CHILE powder in the recipe, not “chili powder”)
If you haven’t tried Portuguese linguiçaor its spicier cousin, chouriço, you are in for a treat. Both are pork sausages, spiced with garlic and paprika, and flavored with port wine. You can grill them like a bratwurst, and they are delicious in soups and stews like traditional portuguese kale soup. Also good on pizza, or in scrambled eggs. Both are commonly found in eastern Massachusetts, and Rhode Island, with their high portuguese populations.
Bratwurst in brötchen the way they are fixed in Germany are outrageously good.
Click here for pics and try not to drool 
There are YouTube videos out there which will show it. But, basically, they just do a very fine grind so that the meat is practically reduced to a paste and then add emulsifying agents to keep it that way.
One of my favourite sausages are called smokies here. They are similar to a bratwurst, usually pork , but also come with mozzarella cheese and Jalapeno embedded within. Cooked slowly over an open fire to crisp the skin, onto the bun (or not), cover in mustard, scarf down!
I’ve never tried the recipe in the link, I posted so you would get the idea of appearance. You can bet I will be though!
Farmer’s sausage is a good starting point to go from as well.
if sausages are uncooked then cooking in water before browning might be better on the stove top. this cooks evenly for safety and texture.
I highly recommend using an instant-read thermometer like this one. I know it seems expensive, but it’s precision built, factory calibrated and eliminates all guesswork when it comes to under- or overcooking foods.
Dammit, now I’m hungry!
Chorizo and egg burrito. No better breakfast anywhere!
Beer.
you want internal temperatures for meat. though you don’t want to puncture the sausage.
you could use a surface reading thermometer, as Chefguy suggested, though you want the surface to be a higher temperature than what the interior temperature is required to be (for a fast cook method in a pan).
you could also go by color change of the item or a time period recommended (for example like 15 minutes after the water has started boiling).
I’m pleased to report that I got some “regular” and “spicy” Italian sausages from the butcher at my local yuppie grocery (no bratwurst there, unfortunately), and fried them up with some cooking wine … and yes, they were tremendous. VERY nice seasoning. Looking forward to trying the other sausage varieties.
ETA - and they didn’t even create any garbage!
Emulsifying agents aren’t really necessary though. Some of the meat proteins (myosin primarily) will do the job without additives. After all, they made frankfurters, mortadella and a host of other emulsified sausages for decades and even centuries out of just meat.
I’m a big fan of Boerewors for a tastier alternative to plain old sausages to take to summer barbies.
Since our local ordinances don’t allow grilling on condo patios or balconies here, we very gently simmer our brats in beer (Leinie’s Honey Weiss is good) to which we add one or two sliced onions and a dash of thyme. Then after about 15 or 20 minutes the sausages go under the broiler or in the George Foreman for browning and the cooking liquid is strained and the onions mixed with spicy brown mustard and maybe a dash of honey and slathered on the cooked brats. Sounds strange but it works, at least for us.
If you really want to be an iconoclast you can use ketchup, Mae Ploy sweet chili sauce and a bit of Sriracha instead of mustard, but Wisconsin will probably deport you and revoke your passport if they catch you doing that inside their borders. 
Next time what you do is take those spicy sausages, remove them from the casings and cook them as little meatballs. Remove when fully cooked. To the pan add fresh tomatoes, basil, oregano, garlic and thyme, season and cook down for about 30 min. Add a splash of red wine and add the meatballs back in. Serve with a green salad and your favourite pasta with some garlic bread and the rest of the red wine you opened… I’ll be over at 6.
Don’t forget the fresh grated Pecorino, Asiago or Romano on top…
I made some of these this past weekend. Minus the fact that I criminally undersalted them (I did some really bad math in my head, and I knew it looked like way too little salt, but all the other ingredients were fine), these were some mighty fine sausages. I wish I had an opportunity to try some when I was in South Africa (or anywhere else that has them), so I could get a baseline idea of what it should taste like, and what the texture should be like. Most of the pictures make it look like it’s fairly coarsely ground, but one Youtube video I found had them double ground through a medium and small plate. I double ground them, but next time, I think I’m just going to go for a single grind and keep it fairly coarse.
I kind of prefer parboiled and broiled sausages to straight-up grilled ones anyway. Usually when people grill them, they do it too hot or something, and they burn on the outside and by the time the inside’s done, they’re usually burst and somewhat burnt.
Broiling lets the entire side of the sausage facing the flames get crisped and browned at once, unlike grills, for some reason.
I like doing them on the grill, but I do them like I do most meats: I make a two-stage fire (or if I’m using someone’s propane grill, I turn off one side of the burners) and cook them slowly up to temperature on that side. Then, I grill them for about a minute or so on the coal side to crisp up and get nice grill marks.
Oh, man, I redid the boerewors today with coarsely ground boneless beef short ribs, lamb, and pork belly, (and the correct 2% by weight amount of salt) and holy crap is that a good sausage.