Preheat your oven to 350°F (175°C) and line a muffin tray with cupcake liners.

In a large bowl, whisk together eggs, brown sugar, neutral oil, sour cream, and mashed pineapple until combined and creamy.

In another bowl, sift together flour, baking powder, baking soda, salt, and cinnamon.

Fold the dry ingredients into the wet mixture, then add shredded carrots and chopped nuts.

Fill each cupcake liner about ¾ full with batter and bake for 18-20 minutes or until a toothpick comes out clean.

Lower the oven temperature to 320°F (162°C). In a food processor, pulse walnuts with flour, brown sugar, and butter until crumbly, then bake until golden.

Beat softened cream cheese, powdered sugar, vanilla, and salt in a bowl, then gradually add cold heavy whipping cream and whip until stiff peaks form.

Frost cooled cupcakes generously with cream cheese frosting.

Press walnut crumble onto the edges of the frosting and decorate with food coloring or rosemary sprigs if desired.