Note: this recipe assumes that you have a big KitchenAid stand mixer
Ingredients:

• 1 package yeast
• 1 cup warm water (I try for about 120°F)
• 2 tbsp sugar
• 3½ cups flour
• 1 tbsp kosher salt
• ¼ cup olive oil (plus a lot more, unmeasured)
• 1 onion
• 1-2 medium-sized tomatoes
• garlic
• Salt, pepper, and other spices to taste (I use 'italian seasoning')

    Put the dough hook on the mixer. Mix the yeast, sugar, and water together in the mixing bowl; let sit for three minutes. If there's no foam and no yeasty smell, you should probably start over; this generally means that the yeast is bad. Slowly add the flour. Add the salt dissolved in a little water and the olive oil. Keep mixing on low until the ingredients begin to look like dough, then turn up the mixer to some moderate speed that seems safe (this will shake the mixer). You may need to pull the dough off the hook occasionally; if the dough is too sticky, add a little more flour. Keep this up for about 10 minutes. Grease a large bowl with olive oil, then put the ball of dough in and turn it in the bowl to cover it in oil. Cover the dough with a damp towel and let it rise for 45 minutes.
    After the dough finishes rising, put olive oil in the baking pan you'll use to cook the focaccia. Stretch the dough out to a ½-inch-thick rectangle, put it on the pan, cover it with plastic wrap, and let it rise for 15 minutes. While it's rising, chop the onion and fry it with olive oil until it starts to carmelize, and chop the tomatoes and garlic.
    Once the 15 minutes are up, uncover the dough and spread the onions, tomatoes, garlic, salt, pepper, and spices on the dough. Bake at 400°F for 15 minutes.