Step 1: Preheat your oven to 350°F (175°C). Grease and flour two 9-inch round cake pans or three 8-inch round cake pans. You can also line the bottoms with parchment paper.
Step 2: In a large bowl, whisk together the flour, granulated sugar, baking soda, and salt. Make sure there are no lumps.
Step 3: In a separate medium bowl, whisk the eggs lightly. Add the undrained crushed pineapple and 1 teaspoon vanilla extract to the eggs and mix well.
Step 4: Pour the wet ingredients into the dry ingredients. Mix with a spatula or spoon until just combined. Do not overmix; a few lumps are okay. Fold in 1/2 cup of the chopped pecans.
Step 5: Divide the batter evenly between the prepared cake pans. Bake for 30-35 minutes, or until a wooden skewer inserted into the center comes out clean. If using 8-inch pans, baking time might be slightly longer (35-40 minutes).
Step 6: Let the cakes cool in the pans for 10-15 minutes before inverting them onto a wire rack to cool completely. Ensure they are completely cool before frosting.
Step 7: To make the frosting, in a large bowl, beat the softened butter and cream cheese together with an electric mixer until light and fluffy (about 2-3 minutes).
Step 8: Gradually add the sifted powdered sugar, 1 cup at a time, beating on low speed until combined, then increasing to medium speed until smooth. Beat in 1 teaspoon vanilla extract.
Step 9: If using, gently fold in the 1/4 cup of well-drained crushed pineapple and the remaining 1/2 cup of chopped pecans into the frosting. Be careful not to overmix, especially if adding pineapple.
Step 10: Once the cake layers are completely cool, assemble and frost the cake. Place one layer on your serving plate or cake stand. Spread a generous amount of frosting over the top. Repeat with the second and third layers (if using three). Frost the top and sides of the entire cake.
Step 11: Garnish with additional chopped pecans or pineapple pieces if desired. Slice and serve this delicious Southern Creamy Pineapple Pecan Cake. Store leftovers in an airtight container at room temperature for up to 2 days, or in the refrigerator for up to 5 days.