Prep: prepare the garlic and onions by chopping the onion and mincing or crushing the garlic. This is the best garlic crusher in the world. If using chuck roast cut up into 2 inch cubes. Season the outside of the beef with salt and pepper. Heat your dutch oven to medium-high heat with oil and sear all sides of the beef until there is crust appearing golden brown. When all sides of the meat have been seared remove the meat and place them aside.
Using the same pot you seared the meat in, cook the onions and garlic. Start the onions a few minutes before the adding the garlic since they take longer to cook. Cook until the onions are becoming translucent and the garlic is fragrant. Don't cook so long that the garlic turns brown.
Add the rest of the ingredients to the pot and blend with a hand held immersion blender or transfer the ingredients to a high speed blender, blend until smooth and replace sauce back to the dutch oven.
Once the sauce is blended and in the dutch oven, replace the beef and place in the oven at 275°F for 3.5 hours for short ribs or 2.5 hrs for chopped chuck roast.
While the beef is cooking you may cook your rice and chop and thinly slice the toppings: red onions, spicy red peppers, fresh cilantro, avocado and wedges of lime.
When the beef is finished cooking, skim off some of the fat off the top. Assemble as pictures show and serve hot.