Preheat oven to 350°F. Using a cupcake pan, add ½ tbsp of rice into the bottom of every other cupcake cup. The rice will keep the cupcake bottoms from browning. Then, add a liner to each cup filled with rice. In the cups that do not have rice, fill with water to about ⅓ full.
Sift all dry ingredients together and set aside.
Combine vanilla, instant espresso powder and egg whites together. Whisk with a fork until combined. Set aside.
In a large bowl, add melted butter, oil, and sugar. Whiz up with a hand or stand mixer using the paddle attachment. Mix on high for 3 mins. Scrape down sides.
Next, add the egg white mixture and mix on high for 3-4 mins occasionally scraping down the sides. The mixture should increase in volume and lighten in colour.
Next, add half your milk and dry ingredients to the mixture. Mix on low until it’s almost combined, then add the rest of your milk and dry ingredients. Continue to mix on low until the last streak of flour is gone.
Take your prepared cupcake pan and add an Oreo to each cupcake liner. Spoon the cupcake mixture over top of the Oreo. The liners should be just over half way filled.
Lightly pack the streusel on top of each cupcake.
Place in the oven to bake for 15-20 mins. To check doneness, insert a skewer. If the skewer comes out clean, they are done.
Once removed, let cool in pan for 15 mins before removing the cupcakes.
Repeat for the next batch. Remember to refill the cupcake pan with water.