
Every single time I whip up this Sweet Potato Gratin, my home fills with the most wonderful aroma. Those soft, layered sweet potatoes sink into a velvety bath of herb-soaked cream, and that bubbling cheese crust on top makes me hungry just imagining it. This dish always vanishes first whenever I serve it at family gatherings, and everyone keeps asking how I made it. The mix of garlic with sprigs of rosemary and thyme creates the ultimate comfort food experience.
The Charm Behind This Heartwarming Gratin
I've tried countless gratin recipes over time, and this one truly stands out. The smooth béchamel wraps around each sweet potato slice while the fresh herbs really wake up all the flavors. I love seeing everyone's reaction when I bring that cheese-topped masterpiece to the table. And you know what's great? Using Reynolds Wrap® lets me spend way less time cleaning up and way more time chatting with my loved ones during dinner.
Your Shopping List
- Sweet Potatoes: Go for large orange ones for the smoothest texture in your layers.
- Gruyere & Parmesan Cheese: This pair creates something truly wonderful together.
- Whole Milk & Cream: They're what makes your sauce so wonderfully smooth.
- Garlic & Shallots: These fill your kitchen with the most wonderful smell.
- Fresh Thyme & Rosemary: Try to get fresh ones if you can find them.
- Reynolds Wrap® Heavy Duty Foil: This will save you tons of cleanup time.
Let's Start Cooking
- Create Your Base
- Soften those shallots in butter, throw in garlic and herbs, then mix in flour, milk and cream. Add both cheeses while stirring until you get a smooth, dreamy mixture.
- Handle the Potatoes
- Cut them into thin slices, about 1/8 inch works best for even cooking.
- Stack Everything Up
- Spread some sauce in your foil-covered dish then start stacking those potato slices, finishing with the remaining luscious sauce on top.
- Baking Time
- Wrap with foil and cook at 350°F for about 60 minutes, then take off the cover, sprinkle more cheese and broil until you see that irresistible golden crust form.
Insider Tricks
Don't rush when cutting those potatoes - even thickness matters. Splurge on fresh herbs if you can, though dried ones will do in a pinch. Make sure your foil wraps tightly so the sauce stays nice and creamy. Let it rest for 30 minutes before digging in. Sometimes I go crazy and use nothing but heavy cream - the extra calories are totally worth it.
Perfect Pairings For Your Gratin
This gratin works beautifully next to holiday favorites like turkey, glazed ham, or even fancy lamb. I usually add some simple green veggies on the side to balance the richness. Grab yourself a glass of creamy white wine and you've got yourself the perfect dinner party meal.

Frequently Asked Questions
- → Can I prep ahead of time?
Sure, you can slice the potatoes and cook the sauce a day early. Keep them chilled separately, then assemble and bake fresh when you need it.
- → Why are my potatoes still firm?
Cut the slices thinner, about 1/8 inch. Cover the dish while baking. If they’re not tender, let them bake longer until soft enough.
- → Can I swap out the cheeses?
Absolutely! Parmesan and gruyere are amazing, but cheddar or fontina work too. Just go for ones that melt easily and taste great.
- → How can I avoid a lumpy sauce?
Pour the milk in slowly, all the while whisking. Stick to medium heat and don’t boil once the cheese is in. Stir till it’s silky.
- → Can I freeze this if I have leftovers?
Yes, but expect some texture changes. Pop it in the freezer for up to 2 months. Let it thaw in the fridge, then reheat covered in the oven.