In a mixing bowl, combine pumpkin purée, mashed banana, brown sugar, vanilla extract, and your chosen ground spices. Whisk until smooth and chill for 30 minutes.

In a food processor, pulse flour, salt, and sugar until combined. Add coconut oil and pulse until it resembles coarse crumbs. Gradually add ice water until the dough comes together, then refrigerate for 30 minutes.

Roll the dough into a rectangle about 1/8 inch thick and slice into 16 rectangles measuring approximately 3x4 inches each. Set aside on a parchment-lined baking sheet.

Spoon pumpkin filling onto one half of each rectangle, dampen the edges with water, and seal with a second rectangle. Press edges with a fork and make small slits for venting.

Refrigerate assembled pop tarts for 1 hour. Preheat oven to 375°F (190°C). Brush tops with almond milk and agave mixture and bake for 25-30 minutes until golden brown.

Mix powdered sugar, almond milk, and maple extract until smooth. Adjust almond milk as needed for desired consistency.

Drizzle icing over cooled pop tarts and sprinkle with maple sugar if desired. Allow icing to set for a few minutes before serving.