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Preheat oven to 375°F. Lightly coat a 9-inch square baking pan with cooking spray. Beat flour, butter, vanilla, (and coconut extract if using), 1 cup of the sugar, and 1/4 teaspoon of the salt with a heavy-duty stand mixer fitted with a paddle attachment on medium-low speed until mixture resembles coarse crumbs, about 1 minute. Reserve 1 cup of the crumb mixture in a small bowl for the topping. Press remaining crumb mixture evenly into bottom of prepared pan.
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Bake crust until golden brown, about 18 minutes. Transfer pan to a wire rack, and cool crust completely, about 30 minutes. (Do not turn off oven.)
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Meanwhile, gently stir together chopped pineapple, cornstarch, lemon juice, and remaining 1/3 cup sugar and 1/4 teaspoon salt in a bowl until thoroughly combined. Spread pineapple mixture evenly over cooled crust.
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Stir together macadamia nuts, coconut, and reserved crumb mixture in a small bowl until combined. Sprinkle this mixture evenly over pineapple mixture on crust. Bake at 375°F until the filling is bubbly and the topping is lightly browned, 45 to 55 minutes. Transfer to a wire rack. Cool completely, about 1 hour, and cut into 16 squares.