Here's the recipe with my substitutions in parentheses:
Makes 18 cupcakes
3 1/2 tbsp soft margarine (or butter)
generous 1/2 cup firmly packed brown sugar (I used organic maple)
2 large eggs
generous 3/4 cup all purpose flour (I used unbleached)
1/2 tsp baking soda
generous 1/4 cup unsweetened cocoa
1/2 cup sour cream (I used plain greek yogurt)
4 1/2 oz semisweet chocolate (I used Trader Joe's chocolate chips)
2 tbsp superfine sugar (organic maple)
2/3 cup sour cream (greek yogurt)
-Preheat oven to 350 degrees. You can use 18 paper baking cases in a muffin pan or I used coconut oil to grease muffin pan since I planned to put cupcakes in the mason jars.
-Put the margarine, sugar, eggs, flour, baking soda, and cocoa n a large bowl and, using an electric hand whish, beat together until just smooth. Using a metal spoon, fold in the sour cream. Spoon the batter into the paper cases or muffin tin.
-Bake the cupcakes in the preheated oven for 20 minutes, or until well risen and firm to the touch. Transfer to a wire rack to cool.
-To make the frosting, melt your chocolate in a heat proof bowl (I melted mine in the microwave for 1 minute at 70 percent power, stirred and then for an additional 30 seconds at 70 percent power). Remove from the heat and let cool slightly, then whisk in the sugar and sour cream until combined. To put in the mason jars, it's less messy to put one plain cupcake in the bottom, then frost, layer another cupcake on top and spread frosting over the top. You can set in the refrigerator before serving. Serve decorated with left-over chocolate chips.
Disclaimer: I am in no way affiliated with the author or publisher of the "Cupcakes" book!