Preheat a grill to high and the oven to 350 degrees F.
Peel the fruit (for the pineapple, also remove the hard core) and slice to 1/2-inch thickness to total 4 cups. Spray the grill with nonstick spray. Grill the fruit just until it releases from the grates and you have nice grill marks, about 2 minutes per side. Remove from the grill and cut into bite-size pieces. Place the fruit in a medium saucepan, and then add the brown sugar, rum, cornstarch and half the salt; gently toss to combine. Bring to a boil over medium-high heat and stir until the sauce starts to thicken and turns from opaque to translucent and shiny, about 3 minutes. Remove from the heat and set aside.
In a separate large bowl, whisk the flour, sugar, remaining salt and nutmeg to combine. Stir the almond flavoring, if using, into the milk. Pour the milk into the flour mixture and stir to form a soft batter.
Brush an 8 by 8-inch glass baking dish with butter. Place the fruit and any accumulated juices into the prepared pan, pour the batter on top of the fruit and spread evenly. Sprinkle the top of the batter with the turbinado sugar. Bake until brown and bubbly, about 45 minutes. Serve warm with a dollop of Whipped Cream.
Chill a whisk and a large metal bowl in the freezer for 15 minutes. Place the cream, sugar and vanilla in the chilled bowl and whip in a figure eight motion until soft peaks are formed.