Preheat the Oven: Preheat your oven to 350°F (175°C) and grease a 9x5-inch loaf pan.
Mix Wet Ingredients: In a mixing bowl, combine the crushed pineapple, granulated sugar, brown sugar, vegetable oil, eggs, and vanilla extract. Stir until well combined.
Combine Dry Ingredients: In another bowl, whisk together the flour, baking soda, salt, and cinnamon.
Combine Mixtures: Gradually add the dry ingredients to the wet mixture, stirring until just combined. If using, fold in the chopped nuts.
Bake: Pour the batter into the prepared loaf pan and smooth the top. Bake for 50-60 minutes, or until a toothpick inserted into the center comes out clean.
Cool and Serve: Allow the bread to cool in the pan for 10 minutes before transferring it to a wire rack to cool completely. Slice and serve, either warm or at room temperature.