Use paper towels to pat dry the brisket. In a small bowl, combine the salt, pepper, garlic powder, paprika, and thyme. Rub the spice mixture all over the brisket.
Preheat a large skillet over medium/high heat. Add the olive oil then sear the brisket on both sides for 2-3 minutes until a nice crust forms.
Place brisket in slow cooker. Top with minced garlic and onion. In a separate bowl whisk the maple syrup, apple cider vinegar, broth, mustard, and tomato paste. Pour mixture over brisket making sure it's about 3/4 of the way covered with liquid. Cook on low for 7-8 hours.
Remove brisket from slow cooker and let rest on wood board for at least 10 minutes. Slice against the grain and serve with the gravy from the slow cooker.