Cut leaves of collards off of stalks and wash individually under cold water. Dry leaves on paper towels. When leaves are dry, create stack of about 20 leaves and roll up. Slice rolls into one-inch wide strips.
Place three cups water in bottom of large steamer pot. Place collards in steamer basket. Pour Guinness over collards.
Toss the collards with garlic, olive oil, white truffle oil, sea salt, pepper, and one tablespoon McCormick’s Season All. Steam on high for 45 minutes, or until collards are tender but still slightly firm. Sprinkle collards with the remaining McCormick’s Season All and serve with dash of pepper vinegar.