Preheat your oven to 350°F (175°C). Lightly grease the bottom and sides of a 9-inch springform pan. For easy removal and to prevent leaks, line the bottom with a circle of parchment paper.

In a medium bowl, combine the graham cracker crumbs and 1/4 cup granulated sugar. Pour in the melted butter and mix until all crumbs are moistened. Press the mixture evenly onto the bottom of the prepared springform pan. You can use the bottom of a glass or your fingers to compact it.

Bake the crust for 8-10 minutes, or until lightly golden. Remove from the oven and let cool slightly while you prepare the filling. Reduce oven temperature to 325°F (160°C).

Wrap the outside of the springform pan tightly with two layers of heavy-duty aluminum foil to prevent water from seeping in during the water bath.

In a large mixing bowl, using an electric mixer on medium speed, beat the softened cream cheese until smooth and creamy, about 2-3 minutes. Scrape down the sides of the bowl.

Gradually add the 1 1/2 cups granulated sugar to the cream cheese, beating until well combined and smooth, about 2 more minutes. Add the sour cream and vanilla extract, mixing until just incorporated.

Add the eggs one at a time, beating on low speed just until each egg is incorporated. Do not overmix after adding eggs, as this can introduce too much air and cause cracks. Scrape down the bowl after each addition.

Gently fold in the well-drained crushed pineapple with a rubber spatula until evenly distributed. Ensure the pineapple is very dry to prevent a watery filling.

Pour the pineapple cheesecake filling over the cooled crust in the foil-wrapped springform pan. Gently tap the pan on the counter a few times to release any air bubbles.

Place the foil-wrapped springform pan into a larger roasting pan. Carefully pour hot water into the roasting pan until it comes halfway up the sides of the springform pan (this is the water bath).

Carefully transfer the roasting pan to the preheated 325°F (160°C) oven. Bake for 60-75 minutes, or until the edges are set and the center still has a slight wobble when gently shaken. Overbaking will cause cracks.

Turn off the oven, prop the oven door open slightly with a wooden spoon, and let the cheesecake cool in the water bath for 1 hour. This slow cooling prevents cracking.

Remove the cheesecake from the water bath and carefully unwrap the foil. Let it cool completely on a wire rack at room temperature for another 1-2 hours.

Once cool, cover the cheesecake loosely with plastic wrap and refrigerate for at least 6 hours, or preferably overnight, until thoroughly chilled and set.

If desired, prepare the sour cream topping: In a small bowl, whisk together the sour cream, 1/4 cup granulated sugar, and 1/2 tsp vanilla extract until smooth. Once the cheesecake is fully chilled, gently spread the topping evenly over the top.

Carefully run a thin knife around the edge of the pan before releasing the springform sides. Garnish with toasted coconut flakes and fresh pineapple wedges, if using. Slice with a hot, dry knife for clean cuts.