Preheat the oven to 350°F. Line two muffin tins with paper liners, or spray with cooking spay. Set aside.
In a large bowl, add the bran cereals and boiling water. Stir until the cereal is well coated in water. Allow to sit and soften and cool completely. Stir this mixture every couple of minutes to help in the cooling process.
Once the bran cereals have cooled (it's ok if it's still warm, you just don't want it so hot that it would scramble the eggs) whisk in the buttermilk, eggs, canola oil, vanilla and brown sugar. Whisk until mostly smooth.
In a separate bowl, add the flour, baking soda, cinnamon and salt. Whisk to combine.
Add the dry ingredients into the large bowl of wet ingredients and stir until just combined.
Mix in the grated carrots, grated apple, raisins, walnuts/pecans and shredded coconut.
Scoop the batter into the prepared muffin tins, filling almost right to the top of the liner.
Bake for 20-25 minutes, or until a toothpick inserted in the centre comes out clean.
