Slow Cooked Beef Tips in Brown Gravy

I like beef.  I like gravy.  I like potatoes.  
This recipe is all of those things.  And since the meat is cooked at a low temperature for a long time, it turns out super tender.  The gravy is simple to make and not at all intimidating.  
Comfort food at it's finest.

2 lbs. tri-tip beef roast cut into 1" cubes
1 medium onion, diced
3 Tbsp. olive oil
3 cloves garlic, chopped
1 1/4 c. beef stock or one can of beef consomme
1 1/4 c. water
2 bay leaves
3/4 tsp. dried thyme
3 Tbsp. butter, softened
3 Tbsp. flour
salt & pepper to taste

1.  Preheat your oven to 300 degrees.  In an oven proof pan with an oven proof lid heat the oil over medium high heat.  Saute the onion for about 3 minutes.  Stir in the garlic.  Season meat with salt and pepper; brown the meat on all sides.  Pour the beef stock and water over the meat.  Sprinkle with thyme and add the bay leaves.  Cover the dish and place in the oven for 2-3 hours.
2.  When the meat is incredibly tender, remove the pan from the oven.  Remove the bay leaves and transfer the meat to separate dish and set aside while you make the gravy.  Mix the softened butter and the flour into a thick paste; whisk this mixture into the liquid in the pan until you get your desired gravy consistency; you may need to add a small amount of water if it's too thick.  Return the meat to the pan and stir to coat the meat.
3.  Serve over mashed potatoes.