Preheat the oven to 425℉ and line one cupcake with baking paper, as these are large muffins we need to ensure the lining is that of a muffin and not cupcake.
In a small mixing bowl add the instant coffee powder and warm water, mix until combined.
Add the melted butter, oil and whisk until smooth. Add the vanilla, brown sugar, castor sugar and whisk. Add the yogurt, milk and whisk until smooth.
Add the dry ingredients (flour, cocoa powder, baking powder, baking soda, salt) and stir together until smooth. Add the chocolate chips and stir well.
Pour into the lined muffin case and top with a few more chocolate chips. Bake at 425℉ for 5 minutes and then bake at 375℉ for 14 minutes on until a tooth pick inserted into the center comes out clean.
While this is getting baked, let us make the ganache, in a bowl add the heavy cream in the microwave and heat for 30 seconds or until hot. Add the chocolate chips, honey and salt into the hot cream and stir together until smooth.
Once the muffin is baked, allow them to a cool a little. Then make a cavity in the center and fill the ganache into the center. Enjoy it warm.