Whatever you do, don’t let Mr. Holmes bake for you. There’s a good reason. Mr. Holmes is a cat. Thankfully, Mr. Holmes Bakehouse in San Francisco belongs to chef Ry Stephen and partner Aaron Caddel, who are much more capable at manning the oven. According to a staffer, the name is just a nod to Grandma’s cat. Whose Grandma owns him was unclear.

The fashionable bakery on the border of Nob Hill and the Tenderloin features white subway tile, “I Got Baked in San Francisco” in neon, Holmes Sweet Holmes on the ground by the door, and stylish gold-on-white takeout boxes. The pastry I first fell for was their buttery donut bursting with salted caramel, which I tried at Fifty/Fifty over the summer. Mr. Holmes built their cred in specialty coffeehouses like that, along with Saint Frank Coffee. Still, that donut, which was really damn good, couldn’t prepare me for this drastically different Cruffin.

The Cruffin ($4.50) isn’t as gimmicky as it sounds. Instead, the towering mushroom-shaped croissant is baked in a muffin tin. Versions change as inspiration strikes, but during my visit, Chef Stephen piped the flaky, sugar-dusted coils with vanilla cream and sweet strawberry jam. The result was addictive, but not an overly rich butter bomb. This is clearly the kind of combo that would be a hit at Wimbledon, and almost certainly will be in San Francisco.