Preheat oven to 350 degrees Fahrenheit and line a 12-cup cupcake pan with paper liners.

In a large bowl, sift together 1 1/2 cups flour, 1/2 cup cocoa powder, 1 cup sugar, 1 teaspoon baking powder, 1/2 teaspoon baking soda, and 1/4 teaspoon salt.

In a separate bowl, whisk together 3/4 cup orange juice, 1/2 cup canola oil, 1 teaspoon vanilla, and 1 tablespoon orange zest.

Pour the wet ingredients into the dry mixture and whisk until thoroughly combined.

Divide the batter evenly among the prepared cupcake liners, filling each cup about 2/3 full.

Bake for 17 to 20 minutes, or until a toothpick inserted into the center comes out clean.

Remove the cupcakes from the oven and let them cool completely on a wire rack.

To make the orange buttercream filling, combine 4 cups powdered sugar, 1/2 cup coconut oil, and 1 tablespoon orange zest in the bowl of a stand mixer.

Beat on medium-high speed until well combined.

With the mixer running, gradually add 1/4 cup orange juice, one tablespoon at a time, until the buttercream reaches your desired consistency.

For the chocolate ganache, melt 1 cup semi-sweet chocolate chips and 3 tablespoons almond milk in a double boiler or in the microwave.

Whisk in 1 tablespoon coconut oil until smooth and glossy.

If desired, make candied orange peel by peeling thin slices of orange zest from the orange using a vegetable peeler.

In a small saucepan, place the orange peels and add 1/2 cup water.

Bring to a boil and cook for 5 minutes.

Drain the water from the orange peels, place them back in the saucepan, and refill with another 1/2 cup of water.

Bring the water to a boil again, cook for 5 minutes, then drain.

Repeat this boiling and draining process one more time to release the bitterness from the orange peels.

In a separate saucepan, bring 1/4 cup sugar, 1/4 cup of water, and the orange peels to a boil, then cook over medium-high heat until the liquid has bubbled away.

Remove from heat and spread the candied peels out to cool on parchment paper.

Once the candied peels have semi-dried (after about 10 minutes), roll them in the remaining 1/2 cup sugar until thoroughly coated.

Store the candied orange peels in the refrigerator or freezer until ready to use.

Once the cupcakes are completely cool, fill each cupcake with the orange buttercream filling using a pastry bag fitted with a narrow tip.

Spread the chocolate ganache evenly over the top of each cupcake.

Top each cupcake with two slices of candied orange peel, if using.