Preheat oven to 350° and line cupcake/muffin pans with paper liners or grease well with non stick spray.
In a stand mixer bowl or large mixing bowl, whisk together the flour, sugar, salt, baking soda and baking powder.
In a medium saucepan, melt butter and cocoa powder together until smooth. Add boiling water and instant coffee and heat just until the edges start to bubble. Do not boil.
Pour the chocolate mix into the mixing bowl with the flour and sugar. Mix on low just until combined.
In a small bowl, whisk together the yogurt, vanilla extract and eggs until smooth. Add this to the mixing bowl and mix on low until fully incorporated.
Increase speed to medium and beat for 30 seconds.
Using a scoop, fill each cupcake liner ¾ full.
Bake for 15-20 minutes or until a toothpick inserted in center comes out clean or with a few crumbs.
Let cupcakes cool in pans for 10 minutes and then remove to cool completely.