These French Onion Crostini taste like mini, hand-held bites of French Onion Soup. You're going to fall head over heels for them. A simple mixture of caramelized onions atop small baguette rounds topped with a crispy blanket of cheese. Perfect for your next party or an easy after-school snack!
The idea for these delicious little bites came a long time ago when we were out to eat. Luke is a huge French Onion Soup fan and orders it almost every time he spots it on a menu. So when we were out at one of our favorite spots, they had a new appetizer on the menu called "Upside Down French Onion Soup". As we talked it over, trying to figure out how they were flipping soup on its head, we envisioned that it would be little toast points topped with a thickened soup and a blanket of cheese.
What appeared on the table wasn't exactly that. More of a skillet of thickened french onion soup served with cheesy toasts, which was perfectly delicious in its own right. But we couldn't stop thinking about that initially imagined dish.
So after a whole bunch of testing, here we have it! Inside-Out French Onion Crostini.
I took our basic go-to French Onion Soup recipe (this classic Ina Garten recipe) and altered it a bit so we could flip it on its head!
We start the process like a traditional soup, using all the classic ingredients and flavors - caramelized onions, thyme, bay leaves, red wine, beef broth. But then we cook it way down and thicken it to embolden the flavor and give it the stability to stay solid-ish atop the toasts. And of course, to make sure they can hold up the blanket of cheese on top as the crostini crisp up under the broiler.
What we end up with is a fancy looking, fancy tasting crostini that's actually easy-peasy!
How to Make French Onion Crostini
We start by caramelizing some onions in butter and olive oil, then let them soften down with some thyme and bay leaf as aromatics. You'll find that the smell as this point is seriously intoxicating.
Then pour in a glug of wine to scrap the bits off the bottom and follow it with some flour to thicken the whole thing. Add in the beef broth, then let it cook down to thicken.
Once thick, split the mixture between the toast slices, top with cheese and let it get crispy under the broiler! Voila French Onion Crostini!
Other Recipe Ideas for a Snack Dinner Night
Crispy Baked Chicken Wings
Easy Oven Fries
Italian Nachos
Charred Scallion and Jalapeno Dip
French Onion Crostini
Ingredients
- 3 tbsp butter
- 1 tbsp olive oil
- 2 onions sliced thinly
- 1 clove garlic chopped
- 1 sprig thyme
- 1 bay leaf
- 1/2 teaspoon sea salt
- 1/4 teaspoon black pepper
- ⅓ cup red wine
- 1 ½ tablespoons flour
- 1 cup beef broth
- 8 baguette slices
- 3 oz shredded Fontina cheese Gruyere, Swiss or Cheddar will also work
Instructions
- Melt the butter in a saute pan over medium low heat. Add the olive oil and let warm.
- Add in the sliced onions, chopped garlic, thyme, bay leaf, salt and pepper over low heat, stirring frequently. Cook until golden brown, approx. 25 minutes.
- Add in the red wine and bring it to a boil. Let the wine cook down until all the liquid is gone (stir frequently). Discard the thyme sprig and bay leaf. Sprinkle in the flour and stir well. Cook for about 5 minutes to get rid of the flour taste.
- Add in the beef broth and stir well. Let cook for 10-15 minutes until thickened.
- Toast the bread. Top with the french onion mixture and a slice of cheese. Place under the broiler for 2-3 minutes (watch carefully!)
can't wait to try this recipe BUT how big should the onions be? Do you use regular yellow onions or the larger sweet onions?
<3 I used medium yellow onions, but whatever you have hanging around will work! It should be about cup and a half of sliced onions (packed), but the recipe's pretty flexible and should work with a little more or a little less.