Slow Roasted Leg of Lamb (Pulpa de Miel la Cuptor)

This is by far my favorite way of cooking lamb.  It is the most tender, moist and juicy piece of meat ever!  I know there's a myriad of marinades and seasonings out there for lamb, but, trust me, this is truly the best.  This is what I grew up with.  Super simple and super flavorful.  Lamb is a strongly flavored type of meat, so it doesn't need much in the way of seasoning.  All it needs is some love in the oven. :)  Enjoy!
-1 (around 4 lbs) boneless leg of lamb, trimmed of all visible fat
-4 Tbs extra virgin olive oil, divided
-salt and pepper
-about 20 cloves garlic, peeled and cut in half, if too big
-2 cups water
Preheat oven to 300 F.
Cut slits all over the lamb. This will ensure perfect cooking throughout the piece of meat.
Place in 9x13 baking dish.  Rub 2 Tbs of the oil on that side of the lamb.  Sprinkle generously with salt and pepper.  Add half of the garlic into the slits.  It should look like this: 
Flip leg of lamb on the other side and repeat the process with the oil, salt, pepper and garlic.  Add the water.
Place in preheated oven and roast, uncovered, for 2 hours, basting a couple of times.  When it's done, the inside meat should look slightly pink and juicy.  This is how it should look: 
Remove from the oven and let it rest for 10-15 minutes.  Slice and enjoy!