Place cauliflower in a large saucepan; add water to cover. Bring to a boil. Reduce heat. Simmer, covered, until tender, 10-12 minutes. Drain; return to pan.
Meanwhile, combine remaining ingredients in a small saucepan. Bring to a boil. Immediately remove from heat and strain; discard garlic, peppercorns and bay leaf. Add broth to cauliflower. Mash to reach desired consistency.