Preheat the oven to 350°F (180°C). Grease an 8x8-inch (20x20cm) baking pan with butter or line it with parchment paper.

In a blender, combine the cottage cheese, Greek yogurt, eggs, honey, melted butter, and vanilla. Blend until smooth and creamy.

Add the oats and pulse briefly so they break down slightly but are not fully pureed.

Pour the blended mixture into a mixing bowl, then add the flour, baking powder, and salt, stirring just until no dry streaks remain.

Add the blueberries and fold gently, just until they are distributed through the batter. Avoid overmixing so the berries do not burst and turn the batter purple.

Pour the batter into the prepared pan and smooth it into an even layer with a spatula.

Place the pan in the oven and bake for 35 to 40 minutes, until the top turns golden brown and the center no longer jiggles when you gently shake the pan.

Sprinkle the sliced almonds over the top during the last 5 minutes of baking, watching closely so they do not burn.

While still warm, drizzle lightly with honey if using.

Let the bake cool completely in the pan before cutting it into squares so the squares do not crumble.