Heat olive oil in a large saute pan over medium high heat.
Brown brisket on both sides (no need to cook all the way through, just until a golden brown crust is achieved on both sides).
While brisket is browning, whisk the broth, salt, pepper, paprika, turmeric and chili powder in a glass measuring cup or small mixing bowl.
Place half of the sliced onions and half of the garlic cloves in the bottom of your slow cooker's ceramic insert.
Place browned brisket on top of the bed of onions and garlic in the slow cooker.
Deglaze drippings in pan with the stock mixture: use a whisk or wooden spatula to scrape up beef drippings from the pan as you add the stock mixture.
Let the broth come to a boil and simmer until it's reduced by half, about 5 minutes.
Pour reduced broth mixture over the brisket in the slow cooker, then place the remaining onions, garlic and bay leaves on top of the brisket.
Secure lid on slow cooker and cook on low for 6-8 hours or until cooked through.
Remove brisket to a cutting board and allow to rest for about 10 minutes, then slice and serve.