Preheat oven to 350°F. Grease and Flour Bundt pan (12 cup size).
In a small dry skillet over medium low heat, add the chopped Pecans and gently shake the pan around occasionally until they smell even more nutty, about 2 - 3 minutes. Remove from heat and set aside.
In a large bowl, mix together the Flour, Sugar and Cinnamon until well combined.
Add the Eggs, Oil and Vanilla to the Flour mixture and mix well. (I use my mixer with the whisk attachment and start on low then increase to medium speed).
Add in the drained, crushed Pineapple, mixing well, followed by the mashed Bananas. Mix until well combined.
Fold in the 1/2 cup of toasted Pecans.
Pour batter into the prepared Bundt pan, distributing evenly around. Bake in the preheated 350°F oven, for 55 - 70 minutes or a cake tester inserted comes out clean. Adjust time accordingly, I usually keep mine in for just over an hour.
Allow to cool at least 10 - 15 minutes in pan, invert onto serving plate and allow to cool completely.