Preheat the oven to 350 degrees F. Pat the short ribs dry and season all over with salt and pepper. Heat the canola oil in a large Dutch oven over medium-high heat. Working in batches, brown the short ribs on both sides, about 8 minutes total. Remove to a plate.
Meanwhile, combine the stock and dried chiles in a medium saucepan and bring to a simmer. Remove from the heat and let steep, 15 minutes.
Discard all but 3 tablespoons oil from the Dutch oven. Add the onion and cook, stirring, until soft, about 5 minutes; add the garlic and cook 1 minute. Pour in the red wine and simmer, stirring, until almost completely reduced, about 12 minutes. To a slow cooker, add the red wine/ onions, thyme and chile-stock mixture and the short ribs. Cook on low 8 hours.
After 8 hours, remove the short ribs to a bowl; shred the meat from the bone. Strain the cooking liquid and pour off the excess fat. Pour the remaining liquid into a skillet and bring to a boil. Reduce to a simmer and cook, stirring occasionally, until thickened, 10 to 15 minutes; season with salt and pepper. Add the meat and toss to coat. Fill the taco shells with the meat; top with cilantro, pickled onions, jalapenos, queso fresco, or sour cream.
Red Pickled Onions
for the Chile Short Rib Taco recipe:
Bring 3/4 cup lime juice, 1/4 cup each red wine vinegar and sugar, and 1 tablespoon salt to a boil in a saucepan. Remove from the heat and let cool, 5 minutes. Toss with 1 thinly sliced red onion in a bowl; cover and chill at least 4 hours, stirring occasionally.
You can find a printable recipe for the taco & onions, here.
Combine wine and fruit in a pitcher, add simple syrup, to taste. Refrigerate for at least 30 minutes and up to 1 day. Serve over ice, garnish with mint and top with a few splashes of club soda, if desired.
Tip: Place a peach or similar fruit on the top of the sangria pitcher to help keep flying & stinging insects away :)