Nothing distinguishes summer better than the triple threat of graham cracker, melted chocolate, and gooey toasted marshmallow. These mini MaryAnn cakes begin with a graham-flavored cake base. They're then filled with a rich, smooth, decadent chocolate ganache, and topped with a marshmallow-like frosting that's then flash-broiled for that quintessential s'more effect.
To make the cakes: Preheat the oven to 350°F. Lightly grease the cups of a 12-cup mini MaryAnn pan. (If you don't have a MaryAnn pan, see "tips," below.)
Weigh the flours, or measure them by gently spooning them into a measuring cup and sweeping off the excess. Whisk together the flours, graham cracker crumbs, cake enhancer, salt, baking powder, and cinnamon; set aside.
Combine the butter, vegetable oil, brown sugar, and honey, beating until the mixture is fluffy.
Beat in the eggs one at a time, scraping the bottom and sides of the bowl after each.
Add half the dry ingredients. Mix to combine, then beat in the milk followed by the remaining dry ingredients.
Divide the batter evenly among the prepared cups of the pan. You may need to bake in batches depending on how large the wells of your mini maryann pan are. The batter should come to within a 1/2" from the top of each well. A jumbo cookie scoop or a scone and muffin scoop could work well here depending on the size of your MaryAnn cups.
Bake the cakes for 15 to 20 minutes, until puffed and firm to the touch.
Remove the cakes from the oven, let cool for 5 minutes, then transfer to a rack to cool completely.
To make the ganache: Heat the cream in a saucepan or in the microwave, until it begins to steam, but doesn't bubble.
Pour the hot cream over the chopped chocolate in a bowl. Let sit for 5 minutes, then stir until smooth.
Divide the ganache evenly among the wells in each of the mini cakes.
Allow the ganache to cool slightly until it starts to set; you can speed this up by putting the cakes in the refrigerator.
To make the topping: Place the egg whites in the bowl of a stand mixer. Alternatively place them in a large mixing bowl (metal preferred), and have your hand mixer ready.
Combine the sugar, cream of tartar, water, and salt in a saucepan. Bring to a boil, stirring frequently until the sugar dissolves.
When the sugar syrup begins to form large bubbles, or after about 3 to 4 minutes of boiling, begin to beat the egg whites to soft peaks (this should take about 3 to 4 minutes). By the time the egg whites are ready, the sugar syrup should be ready to add; if you have a candy thermometer, the temperature of the syrup should be 240°F.
With the mixer running, pour the boiling sugar syrup into the egg whites in a slow stream. Stir in the vanilla, and continue to beat until the frosting is thick and will hold a peak.
Using a piping bag, pipe tall swirls of meringue onto the cooled ganache. The look will be similar to that of a soft-serve ice cream cone.
Set the oven to broil, and transfer the cakes to a baking sheet.
Broil the cakes until the topping is golden brown, 1 to 3 minutes.
Remove the cakes from the oven and serve immediately, for a molten center; or allow to cool before serving.
Store the cakes, covered loosely with plastic wrap, at room temperature for up to 2 days.
