Sweet Potato Gratin with Caramelized Onions & Sage
Serves: ~8-8. Prep time: 20 minutes. Cook time: 55-80 minutes.
Adapted from: The Kitchn (http://s.coop/1v8b1)
Ingredients:
2 Tbsp butter
2 med. onions, peeled & sliced into thin ½ moons, cut ¼" thick
3 lbs sweet potatoes (~3-4 large sw. potatoes)
Salt & pepper
4 garlic cloves, minced
¼ cp + 2 Tbsp fresh or 4 tsp + 2 tsp dried sage leaves, finely chopped
¼ tsp chipotle powder (optional)
1 cp heavy cream, milk or coconut milk
½ cp Parmesan or mild cheddar cheese, grated
Olive oil or sunflower oil
Preparation:
Preheat oven to 375°F.
Heat butter in wide skillet over med-heat. Once heated, add onions. Sprinkle lightly with salt. Slowly caramelize onions until nicely browned all the way through, stirring frequently, ~15-30 mins.
While onions caramelize, slice sweet potatoes into ¼" moons. In lightly oiled 9”x13” casserole dish, lay out one layer of potato rounds that slightly overlap. Sprinkle lightly with salt & pepper.
When onions are caramelized, add garlic & cook until golden. Then add fresh or dried sage, chipotle powder & cream. Mix together well making sure to scrape all caramelized brown bits off bottom of pan. Remove from heat.
Transfer onion & cream mixture in an even layer to casserole dish with sweet potatoes. Layer remaining potatoes on top of onion & cream layer, forming tight, slightly-overlapping rows. Sprinkle lightly with salt & pepper. It will look like there isn’t enough cream – but resist the impulse to add more. Cover casserole dish tightly with tinfoil.
In preheated oven, bake casserole for 25-30 mins. or until potatoes are just tender & cream is golden brown & bubbling. NOTE: baking time completely depends on how thick potatoes are cut. If potatoes are sliced thicker than ¼", increase baking time!
Remove from oven & remove tinfoil. Sprinkle cheese & remaining sage over top of gratin & drizzle lightly with olive or sunflower oil. Return the uncovered dish to oven for ~15-20mins. or until brown & crispy. Remove from oven & let cool for a minimum of 15mins. before slicing & serving.