Preheat the oven to 350°F (180°C).
In the bowl of a stand mixer with the paddle attachment, combine the salted butter, canola oil and granulated sugar until well combined.
1/4 cup (56g) salted butter, melted, 1/4 cup (60mL) canola oil, 1 cup (230g) granulated sugar
Add in the eggs, one at a time, mixing thoroughly between each addition.
2 eggs, room temperature
Once mixed in, add the vanilla extract and butter flavor.
1/2 Tbsp vanilla extract, 1/4 tsp butter flavor
In a separate bowl, whisk together the cake flour, all-purpose flour, baking soda, baking powder and salt.
1 cup (139g) cake flour, 1/4 cup (38g) all-purpose flour, 1/4 tsp baking soda, 1/4 tsp baking powder, 1/2 tsp salt
Add the dry ingredients to the mixer and slowly begin to incorporate. Once the dry ingredients are almost all combined with the wet ingredients, slowly pour in the buttermilk and mix until well combined and smooth.
2/3 cup (177mL) buttermilk, room temperature
Divide the batter into mini silicone muffin molds, filling each 3/4 of the way full.
Bake for 17-20 minutes or until the cake springs back when tapped or a tooth pick comes out with some moist crumbs on it.
Allow to rest for 5 minutes and then turn the bites out onto the counter. Let them continue to cool while making the icing.
Add the milk and butter to a microwave safe bowl and microwave for 45 seconds or until bubbling and hot.
¼ cup (59mL) milk, 10 Tbsp butter
Whisk in the vanilla and powdered sugar. Add more milk to thin, if needed. If using white food coloring, mix until incorporated.
2 tsp clear vanilla extract, 3 1/2 cups (375g) powdered sugar, White food coloring, if desired
Scoop and gently spread the icing onto the top of each cupcake and top with sprinkles.
sprinkles
Allow the icing to set and then serve. Store in an airtight container for up to 4 days or in the freezer for up to 3 months.