Slow Cooker Brisket

Bahan-bahan (8 porsi)

• 1 medium yellow onion (sliced)
• 4 cloves garlic (coarsely chopped)
• 1 tablespoon olive oil (or as needed)
• 4 pounds brisket
• 1 tablespoon chili powder
• 1 tablespoon brown sugar
• 1 teaspoon salt (or to taste)
• ¾ teaspoon onion powder
• ½ teaspoon black pepper
• ¾ cup barbecue sauce
• ¾ cup chili sauce ( *see note or additional BBQ sauce)