Preheat oven to 350F.
Drizzle 1-2 tbsp olive oil in an oven safe pot (or dish) with a lid.
Slice 1 medium yellow onion into thin slices and add it to the pot with 3-4 chopped garlic cloves.
Add 3lb of chuck roast and season with 3-4 generous pinches salt, fresh cracked pepper, 2 tbsp taco seasoning, and 4 individual adobo chipotle peppers (canned, in the sauce).
Pour in 1 can of tomato sauce (15oz) and 18 fluid ounces beef broth.
Cover, then place in the oven covered at 350F for 4 hours.
After 4 hours, remove the chuck roast from the oven, shred using two forks, mix well with the drippings.
To make the mashed parsnips, cut 2 medium parsnips into thin slices (yields about 3 cups). Bring a pot to medium-low heat, add 1 tbsp olive oil, add the parsnips, add 2 thinly sliced garlic cloves, 1 cup heavy cream, and 2 generous pinches of salt. Mix, then cover for 20-30 minutes. Stir occasionally, then put the lid on. When its done, add fresh cracked pepper, then mash it a fork and spread at the bottom of a serving dish.
To make the sauce, process 3 tablespoons sour cream, the juice of 1 large lime, 2 adobo chipotle peppers and 1 tbsp of the sauce, 1 large handful cilantro, 1 garlic clove, 1 tbsp onion powder, 2 generous pinches of salt, and ⅓ cup water.
Plate this up with the mashed parsnips at the bottom, the meat on top, add some sauce, and top with fresh cilantro or parsley.