Preheat oven to 350°F. Place rack in center of oven. Spray 10-cup Bundt-style pan generously with nonstick cooking spray. Set aside.

In a large bowl whisk together sifted flour, baking powder and salt. Set aside.

Spread coconut on parchment lined baking sheet. Bake for 6-8 minutes, stirring coconut with a fork every few minutes to promote even browning. When done toasting let cool on tray then place in food processor and pulse until finely chopped.

Using handheld mixer beat butter for 1-2 minutes until light and fluffy. Add sugar and beat for another two minutes until well combined. Add the eggs one at a time, making sure to beat mixture well after each egg is added. Beat in vanilla, lime zest, key lime juice and toasted coconut. With a spatula add the flour mixture to the butter mixture alternating with the buttermilk, beginning and ending with the dry ingredients. After each addition just mix until combined. Do not over mix.

Pour the batter into the prepared pan and spread evenly with a spatula. Bake for 45-60 minutes or until cake tester comes out clean. Check at 45 minutes so you do not overbake or your cake will be dry. Cool in pan on wire rack for 5-10 minutes.

While cake is cooling make the glaze. In a small saucepan over medium heat combine the key lime juice and sugar. Cook until the sugar is dissolved. Set aside.

Turn the cake out onto a wire rack placed over a baking sheet. Poke the cake all over with a cake tester or a toothpick. Brush the glaze over the entire cake letting it sink in until all the glaze is finished.

Let cake cool before slicing. Serve with whipped cream if desired.