As you can see in the comments, I asked the author about the 1 tablespoon of baking powder. Her response was that it was deliberate and it is indeed what she uses.
I made 3 batches today - the chocolate muffins, the cranberry orange, and zucchini muffins from my own recipe. The cranberry got 3 teaspoons (1 tablespoon) of baking powder, the zucchini got 2 teaspoons, and the chocolate got 1. My baking powder is relatively new and I know it has been performing well based on other recipes I've made recently.
Height-wise, the chocolate did best (1 teaspoon). This muffin had a fairly light batter, so I'm not really surprised. I overbaked them a bit so the texture isn't ideal. I don't know if I would call them "fudgy," but they have a nice chocolate flavor without being overly rich. It is, after all, a muffin and not a cupcake. Big hit with my small child, though, who loves anything chocolate.
Taste-wise, the cranberry orange muffins (3 teaspoons/1 tablespoon) get the vote. Tangy and sweet with an aroma that brought my family to the kitchen. Not a huge amount of height (although a heavy batter) and just a bit on the tough side for texture. (I was very careful not to overmix; I bake a lot of quick breads.) Very happy overall.
Texture-wise, the zucchini muffins (2 teaspoons) were the winner. They didn't rise much, but my ingredients were a bit off and the zucchini may be the culprit here - I usually use that recipe for quick bread rather than muffins.
Final decision? Gosh, I'm just not sure. I can say that I did not get the bitter flavor I was half-expecting from the larger amounts of baking powder. I also can't say that any of the negatives were due to the baking powder. All in all, when I use these recipes in the future, I'd say I would probably be okay with either using the recipe as written or using 2 teaspoons. Either way, back up to 4 it goes.
***ORIGINAL REVIEW FOLLOWS***
When I see Marg's name, I know that there's a good chance that I'm going to find some useful recipes. I've obtained, used, and reviewed some of her other books.
I would have liked to have seen some information on greasing versus greasing and flouring muffin tins, and possibly some freezing information, but ultimately, the book says it has recipes and it delivers on that.
The format is clean with each recipe appearing on one page. Each recipe has a little comment from Marg which is a very nice touch.
I really, really want a Fudgy Chocolate Muffin **right now**. The savory muffins also sound very appealing and I was actually delighted to see something other than sweet and fruity.
One quibble - some recipes say they make 18 muffins, and others say they make "12 large" muffins. I have regular muffin pans and I have pans that make very large muffins (like the size they offer at Perkins). If different sizes are being used, this should be referenced. Otherwise, a little bit of explanation about the difference between "18 muffins" and "12 large muffins" would be a good idea.
I liked it, am keeping it, and will be using it.