Puree sundried tomatoes and diced jalapenos (keep seeds if you want spice) in a food processor with a dozen pulses (until desired texture is reached). Add to the fridge to keep very cold until ready to use.
Cut turkey thigh and fat into chunks, ideally when still partially frozen. Put through a coarse grinding plate, add to the freezer if necessary to keep cold, then grind one more through a fine grinding plate. Add to the freezer to get closer to 32 degrees, then prepare to mix.
Make sure sherry is 32 degrees when you're ready to begin mixing. Using a meat mixer, add spices as you mix, along with ice-cold sherry. Meat is mixed properly when it is tacky and will stay sticking to your palm in golf-ball size and help upside-down.
Place mixed meat in the freezer until ready to stuff. Follow respective casing directions to prepare them, and, once ready to stuff, slide casings onto the stuffer. Load stuffer with cold meat and begin stuffing casings. Carefully pop any air bubbles with a sausage pricker.
Spin into links, alternating spin direction with each link to keep them tight. Hang for a few hours in the fridge.
To cook, preheat oven to 300 degrees and cook sauages for 30 minutes. Enjoy!