Preheat the oven to 350°F (175°C). In a mixing bowl, combine flour, softened butter, sugar, and salt. Mix until crumbly.

Press the mixture into the bottom of a greased 9x9 inch baking pan to form an even crust.

Bake the crust in the preheated oven for 10 minutes.

In a clean bowl, whisk together the eggs and sugar until well combined.

Add the crushed pineapple, flour, vanilla extract, and baking powder. Mix until smooth.

Pour the pineapple filling over the pre-baked crust.

Return to the oven and bake for an additional 20 minutes, or until the filling is set.

Allow to cool before cutting into bars.