These were baked by Keith Boyden using this recipe.
Some more of Keith Boyden's work.
This picture shows some of the thinner oven-bottom muffins. Note the bagel-like hole in the middle.
These ones are like the "fluffier" commercial muffins, but are floury. Also they don't have a hole.
Here are some wholemeal muffins.
This is typical packaging. There's no labelling and no ingredients list, so there could be anything in there!