Slurry
Slow cookers meals are sometimes more "watery" than we'd like. When this happens we use a slurry to thicken the sauce.
A slurry is a cold liquid mixed with flour or cornstarch - use whatever's at hand.
Put the flour (about 1 T) or cornstarch (about 1/2 T) in a bowl add a cup of water. Mix it up with a fork. Stir the slurry into the slow cooker and let it cook for awhile to thicken.