01 -
Preheat oven to 350°F (175°C). Grease 12 muffin tins well and dust with cocoa powder.
02 -
Sift together the flour, cocoa powder, and baking powder. Set aside.
03 -
In a stand mixer with the whisk attachment, whisk the egg, sugar, and vanilla extract on high speed until foamy and slightly stiffened.
04 -
Mix melted butter and vegetable oil in a measuring cup. Slowly pour into the egg mixture in a steady stream while whisking.
05 -
Combine whipping cream and lemon juice. Slowly add to the mixing bowl at a reduced speed.
06 -
Fold in the dry ingredients by hand using a rubber spatula. Do not overmix; lumps in the batter are acceptable. When nearly incorporated, gently fold in chocolate chips and cherries.
07 -
Pulse crumble ingredients in a food processor or rub together by hand until a crumbly texture forms. Press the mixture in your hand and break small pieces over the muffin batter in the pan.
08 -
Spoon the batter into greased cocoa-dusted muffin tins. Top with crumble and bake for 25–30 minutes or until a toothpick inserted into the center comes out clean.
09 -
Let muffins rest in the pan for 5 minutes before transferring to a wire rack to cool completely.