Preheat the oven to 160 degrees.
Grease and lightly flour, or lined with parchment paper, a mold of 25x32 cm (13x9 inch).Sift the flour and yeast into a bowl.
Melt the butter and chocolate in the microwave or in a double boiler. They should be smooth.
In a bowl or in the mixer, pour the butter and the chocolate, add the sugar and the eggs one at a time. Incorporate, a little at a time, the sifted flours and salt with a spatula to obtain a homogeneous mixture.
Pour everything into the pan and level.
Cook for 30/35 minutes, the appetizer should not come out completely dry. It is important not to overcook the brownies.
Let it cool in the mold for a few minutes before transferring it to a grate to cool completely for at least a couple of hours.
Spread the glaze at room temperature (it must not be cold because it would be difficult to spread it) with a spatula.
Cut the brownies into squares and spread the glaze at room temperature with a spatula.