Whisk all of the dry ingredients in a large bowl and set aside.
In a medium bowl, whisk together the oil, butter, white and brown sugar, egg and vanilla.
Add the shredded apples and carrots to the wet ingredients, mixing them until evenly distributed in the mixture.
Make a well in the dry ingredients and add the wet mixture to it, folding the batter together with a spatula until just combined. If the batter is lumpy, that's okay.
Portion the thick batter into muffin tins and bake in a 375 F oven for 20 to 25 minutes until a toothpick comes out clean and the muffin is golden brown.
Serve warm, with a pat of butter and embrace all that fall has to offer!
Recipe by The Chewy Life at https://www.thechewylife.com/apple-and-carrot-autumn-muffins/