Stir together flour, garlic powder, salt and yeast in a medium bowl. Add the olive oil to flour mixture and lightly mix. Dissolve squid ink in the warm water and add to the flour mixture, and mix with a fork until it comes together into a shaggy dough. Use your hands to work the loose flour into your dough while in the bowl until its mostly incorporated. Turn it out on a floured surface and knead lightly, forming the dough into a ball. Clean and dry the bowl you used to mix the dough. Oil the bowl and place the dough in it and roll to coat the dough with oil. Cover with plastic wrap and set aside to double in volume. About 2 hours.

While dough rises, grate cheese, prepare mushrooms skulls toppings, and balsamic glaze.

When dough has doubled, remove from bowl and cut into 4 equal pieces and shape into a ball pinching edges together. Push in a circular motion to form a taut ball. Repeat with the remaining pieces. Brush each with oil, cover with plastic wrap and let rest for 10 minutes. (Note: Only 2 of the 4 are pictured below)

Create two skull faces on opposite sides of each mushroom using a straw to form the large eye holes. Use a pairing knife to cut the nose holes and to scrape down the stem to create teeth. Trim the stems if desired. Once you've made skull faces on both sides of each mushroom, cut each mushroom in half to create two skull halves.

Melt butter in a large skillet, add mushroom skulls and sauté about 5-8 minutes. Add shallots, garlic and sherry and continue to cook until all the liquid has cooked down, about 3-5 minutes more. Add thyme leaves, salt and pepper and set aside.

Over medium heat, reduce the balsamic vinegar to about 1/3 cup. Cool and add honey to taste. Set aside.

Place a pizza stone or a rimless cookie sheet on the bottom rack of the oven and preheat oven to 500 degrees.

Cut a length of parchment paper. Coat hands with oil and gently pull one piece of dough into an 6 inch length. Place it on the parchment paper and gently dimple surface of dough with fingertips and then flatten with your palms into a 8" by 4" oval. Repeat with remaining dough. Brush each flatbread generously with pesto sauce, grated Pesto Gouda cheese, and the mushroom and shallot mixture.

Transfer the parchment with the flatbreads onto the pizza stone, or cookie sheet and bake for 10-12 minutes. To remove from the oven, pull the parchment paper with flatbread on it onto another cool baking sheet. Transfer to a cutting board and let cool 5 minutes then cut crosswise into triangles. Top with your favorite fresh herbs and drizzle with the Balsamic glaze. Bone Appetit!