Preheat your oven to 350°F (175°C) and line a 9x13 inch baking dish with parchment paper.

In a medium-sized bowl, combine almond flour, coconut flour, salt, vanilla extract, maple syrup, and melted coconut oil. Mix until the ingredients form a crumbly texture.

Press three-quarters of this mixture evenly into the bottom of your prepared pan.

Place the pan in the preheated oven and bake for 10-12 minutes until lightly golden.

In a medium saucepan over medium heat, combine sliced strawberries, chopped rhubarb, lemon juice, maple syrup, and salt. Simmer for about 7 minutes.

In a small bowl, whisk together tapioca starch and water until smooth. Gradually add this to the saucepan, stirring constantly until thickened.

Spread the filling evenly over the baked crust, leaving a ¼ inch border. Crumble the remaining crust mixture over the filling.

Return the assembled bars to the oven and bake for an additional 20 minutes until topping is golden brown.

Mix melted coconut butter, maple syrup, vanilla extract, and lemon juice in a bowl until smooth for the glaze.

Pour the glaze over the bars once cooled and let them set for at least 2 hours at room temperature.