In a small blow, place the chia seeds and water, and let it rest for 20 minutes, until the chia seeds absorb the water.
Preheat the oven to 375°F (180°C).
In a small bowl, sift together the almond flour, cocoa powder and salt, and set aside.
In another bowl, beat the butter and sugar, either with a mixer or by hand using a whisk, until it turns fluffy and lightens in color. Beat in the vanilla.
Add the chia seeds to the mixture, and fully incorporate using a rubber spatula.
Now, add the dry ingredients to the mixture in three different additions, mixing after each addition using the rubber spatula.
In a previously greased square baking pan about 9x9 inch (or a rectangular one of similar proportions) pour and spread the batter. Llevar al horno por 20 a 25 min. aproximadamente.
Bake at 375°F (180°C) for 20 to 25 min.
After baking, let them cool down completely. Then cut into 2x2 inch (5x5 cm) squares aprox. and enjoy.