Hi Frances. Since the muffins in your pic look like actual chocolate muffins, you might have left off an ingredient or two when transcribing your recipe. Did you use melted chocolate? or maybe cocoa powder with additional milk? I was going to tweak for cocoa powder, but I instead decided to try it more or less as written, since I love spice-speckled food. :-) Here's what I did:
Preheat the oven to 425°F. Combine 2 cups of Bisquick and 3 tablespoons of Splenda in a small bowl and set aside. Place 2 tablespoons of butter in a two-cup liquid measuring cup and microwave to melt, about 20-25 seconds. Add 3/4 cup milk, which should cool the butter enough that you can then add two eggs. Beat lightly with a fork. Stir in 1/2 teaspoon vanilla (I like vanilla in baked goods). Pour the liquids into the dry ingredients, and combine with a rubber spatula, being sure to scrape the sides and bottom of the bowl. Don't over mix. Stir in 3/4 cup chocolate chips and 5 teaspoons spearmint tea.
I didn't feel like climbing up to get muffin tins, so I buttered a 9-inch pan and poured in the batter. Sprinkle a few extra chocolate pieces on top if you have them. Bake at 425°F for eight minutes and then lower to 350°F for 10 minutes. Test to see if done. Your kitchen should smell nice and minty.
I definitely think it's tasty, and I would try it again. The next time I might add an extra teaspoon of mint and possibly the missing chocolate. :-)