In the bowl of a stand mixer fitted with a dough hook attachment, add the flour, yeast, sugar and garlic salt. Mix until combined.

In a microwave safe bowl add the beer. Microwave on high for 20 seconds, test temperature with a cooking thermometer and repeat until temperature reaches between 120 and 125 degrees Fahrenheit.

Add the beer to the stand mixer and mix on medium speed until most of the flour has been moistened.

Turn speed to high and beat until dough is smooth and elastic, about 8 minutes.

Transfer dough to a lightly oiled bowl, tightly wrap with plastic wrap. Allow to sit in a warm room until doubled in size, about 45 to 60 minutes (while the dough rises, start the onions).

Remove from bowl and add to a lightly floured surface. Knead several times, cut into 6 equal sized pieces.

One at a time form the dough into 6 inch circles. Place on a baking sheet that has been covered with parchment paper.

While the dough is rising, make the onions. In a saucepan or Dutch oven melt the butter with the olive oil over medium heat. Add the onions with a pinch of salt and sugar, cook until softened, about 10 minutes. Add beer and cook, stirring occasionally, until the beer has mostly evaporated and turned to a glaze about 20 minutes. Make sure to keep the heat low or the onions will burn before they caramelize.

Preheat the oven to 400.

Add the tomatoes to a small bowl. Toss with olive oil, salt and pepper, set aside.

Top the 6 flatbreads with slices of Gouda, then add about ¼ cup of caramelized onions, then tomatoes.

Brush exposed crust with olive oil.

Bake at 400 for 12-15 minutes or until crust has turned golden brown.

Sprinkle with parsley just before serving.