Caramelized Onion and Mushroom Flatbread

Caramelized Onion and Mushroom Flatbread

I love pizza (aren't there t-shirts that say that?) All types of pizza; pan crust, hand tossed, stuffed, thin crust, sauce, no sauce, loaded with meat or just veggies. Pizza can be wonderful and comforting and a great end to a stressful day, or it can be a disappointment. I know you understand; the lukewarm delivery where half the cheese is stuck to the inside of the box. Or a haphazard frozen pizza that's been forgotten about for a minute too long and burned around the edges.

Seattle has some great pizza places. Our favorite is Serious Pie, a Tom Douglas restaurant. If you're not familiar with Tom Douglas, he's a Pacific Northwest culinary genius. His restaurants and culinary influence are all over the city, and his pizza place makes some really excellent pizza. All wood fired with local ingredients, they never disappoint.

However, on a rainy evening or a lazy Saturday, when my introverted self just can't handle the noisy bar atmosphere of Serious Pie, I still want a great pizza. This is my homage to that pizza. Rustic, loaded with great ingredients, every bite is perfect.

Great pizza starts with great crust and great crust takes time. Dissolve 1 tablespoon of active dry yeast and 1 tablespoon of sugar in 1 cup of warm water. I use my meat thermometer to make sure the water is between 105 and 115 degrees. Allow the yeast to bloom for 5-10 minutes.

In a food processor (or by hand) combine 3 cups of flour, 1 teaspoon of salt, 1 tablespoon of dried basil and 1 tablespoon of dried oregano. Pulse to combine.

With the blade running, drizzle in 2 tablespoons of olive oil followed by the yeast/water mixture until a smooth ball of dough forms.

Place ball of dough in an oiled bowl and cover with a clean kitchen towel. Allow to rise 1 1/2 hours in a warm spot until doubled in size. My trick is to preheat my oven to the lowest possible setting then turn it off. I place the dough in this warm environment (oven off of course!) and get a good rise every time.

While the dough is rising, start the caramelized onions. Just like the dough, these need time. Rushing caramelized onions ends in overcooked and burned bits instead of creamy sweet onions; almost and onion jam.

Slice one large sweet onion thinly. Heat 2 tablespoons of butter in a medium skillet over medium low heat. Add onions and sprinkle with 1 tablespoon of sugar. Resist the urge to stir the onions too often. They will take a full 45-60 minutes if done properly.  

When the onions have cooked down, add 8 oz of chopped mushrooms. I used locally foraged hedgehog mushrooms but chanterelles would be really nice, or even just crimini mushrooms. If you can get your hands on them, morels would be amazing in this recipe.

Once the mushrooms have cooked down, add 1/4 cup of heavy cream and season with salt and pepper. Simmer until the cream has reduced by half.

Preheat oven to 475 degrees. Divide risen dough in half and roll out into a long oval on a floured surface. Sprinkle a tablespoon of cornmeal over a parchment lined baking sheet, and move dough to sheet. Brush with olive oil.

Spread half of the caramelized onions and mushrooms over the dough. Top with shredded fontina cheese, or if you can find it, half fontina and half truffle cheese. Thank you Trader Joes for truffle cheese! I used about a cup of shredded cheese per flatbread; more or less can be used per preference.

Bake the finished pizza in preheated oven for 10 minutes or until crust is golden brown and cheese is bubbling and started to brown.

This recipe makes two flatbread pizzas. One is certainly enough for the two of us, so instead of baking the second, I froze it on the baking sheet for an hour until it was easy to wrap in a double layer of plastic wrap. Ryan was able to make the second pizza as a homemade frozen pizza while I was out of town. Preheat oven to 475 and place frozen pizza on a non stick baking sheet and bake 10-15 minutes or until browned. Just as good baked from frozen, I would expect this pizza would keep well in the freezer for at least a month. Longer if you had access to vacuum seal the pizza after freezing.

Enjoy this caramelized onion and mushroom flatbread with a great glass of wine and a spicy arugula salad. Perfect!


Caramelized Onion and Mushroom Flatbread

By , March 22, 2015
Prep time: 2 hours Cook time: 10 minutes Yield: 4 servings
Sweet caramelized onions and mushrooms on an herbed crust with creamy fontina cheese. Perfect pizza! pizza, onions, mushrooms, fontina


  • 1 tablespoon of active dry yeast
  • 1 tablespoon of sugar
  • 1 cup of warm water (105-115 degrees)
  • 3 cups of flour
  • 1 teaspoon of salt
  • 1 tablespoon of dried basil
  • 1 tablespoon of dried oregano
  • 2 tablespoons of olive oil
  • 1 sweet onion
  • 2 tablespoons of butter
  • 1 tablespoon of sugar
  • 8 oz of mushrooms (crimini, hedgehog, chanterelle, or shitake)
  • 1/4 cup of heavy cream
  • Salt and pepper
  • 2 cups of shredded fontina cheese
  • 2 tablespoons of cornmeal


  1. In a small dish, combine yeast, sugar, and warm water; stir to dissolve yeast and allow to bloom 5-10 minutes
  2. In a food processor (or by hand) combine flour, salt, dried basil and oregano; pulse to combine
  3. With the blade running, add 2 tablespoons of olive oil; add yeast/water mixture and process until a smooth ball of dough forms
  4. Place dough in a oiled bowl and cover with a clean kitchen towel; place in a warm spot and allow to rise 1 1/2 hours or until doubled
  5. Heat 1 tablespoons of butter in a medium sized skillet; slice onion thinly and add to pan
  6. Sprinkle onions with 1 tablespoon of sugar and cook over medium low heat until softened and caramelized, about 45 minutes
  7. When onions are caramelized and cooked down, add 8 oz of chopped mushrooms; cook down 5-7 minutes
  8. Add 1/4 cup of heavy cream and season with salt and pepper, simmer until reduced by half; remove from heat and cover to keep warm
  9. Preheat oven to 475 degrees
  10. Divide risen dough by half and roll each half into a long oval or rectangle; place on a parchment lined baking sheet sprinkled with 1 tablespoon of corn meal
  11. Spread half of the onions and mushrooms over each crust, sprinkle each with a cup of shredded cheese (more or less based on preference)
  12. Bake in preheated oven 10 minutes or until crust is browned and cheese is bubbling

Sharing our culinary adventures in Cascadia with simple, sustainable & satisfying eats. Bon Appétit!