Preheat your oven to 180°C (350°F). Line the bottom and sides of your 9-inch square baking pan with parchment paper, leaving a slight overhang for easy lifting.
In a large mixing bowl, combine the oats, salt, and brown sugar. Stir well to evenly distribute the dry ingredients.
Melt the butter in a small saucepan over low heat until just fragrant and smooth. Pour the melted butter into the oat mixture, then add the honey or maple syrup.
Stir the mixture until everything is coated and sticky, then press it firmly into the prepared pan, spreading it out evenly with a spatula or your fingers.
Bake the base in the oven for about 15 minutes, or until it turns golden around the edges and smells toasted.
While the base bakes, slice the bananas into thin rounds.
In a skillet over medium heat, melt a tablespoon of butter. Add the sliced bananas and cook, stirring occasionally, for about 5 minutes until they are fragrant, golden, and jammy, with some caramelized edges.
Remove the baked oat base from the oven and carefully spread the caramelized bananas over the hot crust, pressing them gently into the surface.
Return the pan to the oven and bake for another 10–12 minutes, until the bananas are bubbling and slightly caramelized around the edges.
Remove from the oven and let the bars cool completely in the pan for about 20 minutes. Then, use the parchment overhang to lift out the bars and transfer them to a wire rack.
Once cooled, cut into squares with a sharp knife. Serve directly or store in an airtight container for up to 3 days for a delicious, gooey treat.
