Creamy Potato & Broccolini Gratin
✨ Why This Recipe Works
A cozy one-skillet gratin: golden potatoes and tender broccolini baked in a silky mustard-cream sauce with nutmeg, finished with a bright parsley-lemon pesto.
Crafted with everyday pantry staples and perfected in Mery's home kitchen, this Creamy Potato & Broccolini Gratin brings authentic comfort and vibrant flavors straight to your table. Every step has been carefully timed and measured so home cooks of any skill level can recreate foolproof, delicious results with ease.
With a quick 15 minutes of prep and 35 minutes of cooking, this wholesome dish balances ease and rich flavor without requiring complicated culinary equipment.
📜 Deep-Dive Food History • 🌲 Wild Foraging & ASMR Cooking • 🍲 Ancient Recipes Brought to Life
🥗 Ingredients (tap to check off)
For the Potato & Broccolini Gratin
- 1½ lbs small waxy potatoes, whole and scrubbed
- 1 bunch broccolini (about 8 oz), ends trimmed
- 2 tbsp kosher salt (for potato boiling water)
- 1½ cups heavy cream
- 1 cup sour cream
- ½ cup crème fraîche
- 1½ cups shredded Gruyère cheese, divided
- 1 tbsp whole-grain mustard
- ½ tsp freshly grated nutmeg
- ½ tsp freshly cracked black pepper
- 1 tsp kosher salt
For the Quick Parsley-Lemon Pesto
- ½ cup finely chopped flat-leaf parsley
- Zest of 1 fresh lemon
- ¼ cup extra-virgin olive oil
- Pinch of fine sea salt
👨🍳 Step-by-Step Instructions
Par-Boil the Potatoes & Broccolini
Bring a large pot of salted water to a rolling boil. Add the scrubbed potatoes and cook until just tender, about 12 to 15 minutes. Add the broccolini for the last 3 minutes of boiling, then drain thoroughly in a colander.
Preheat Oven
Preheat your oven to 400°F (200°C).
Whisk the Velvety Cream Sauce
In a large oven-safe cast iron skillet, whisk together the heavy cream, sour cream, crème fraîche, whole-grain mustard, freshly grated nutmeg, 1 tsp salt, and black pepper. Stir in ¾ cup of the shredded Gruyère cheese until evenly combined.
Nestle Vegetables & Top with Cheese
Nestle the cooked potatoes and broccolini into the rich cream sauce, then scatter the remaining ¾ cup of Gruyère cheese evenly across the top.
Bake to Golden & Bubbling
Bake at 400°F (200°C) for 15 to 20 minutes, until the cheese is deeply golden-brown and bubbling enthusiastically around the edges.
Stir Pesto & Serve Hot
While the gratin bakes, stir the finely chopped parsley, lemon zest, extra virgin olive oil, and a pinch of salt together in a small bowl into a loose herb pesto. Spoon generously over the hot gratin and serve piping hot straight from the skillet.
❄️ Storing & Reheating Leftovers
Refrigeration: Allow the dish to cool to room temperature, then store in an airtight glass container in the refrigerator for up to 3 to 4 days.
Reheating: Reheat in a skillet over medium-low heat with a small splash of water or olive oil, or in a 350°F (175°C) oven until thoroughly warmed. This preserves the delicate moisture without drying out the texture.
🍳 Recommended Kitchen Equipment
Kitchen Note: Having the right kitchen tools ensures foolproof results. We recommend items tested in our own home kitchen.
📊 Nutritional Breakdown (Per Serving)
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⭐ Tried This Recipe? Rate & Review
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