Equipment
Ingredients
Grain Base
- 150 g pearl barley, rinsed
- 475 ml vegetable broth
Vegetables & Aromatics
- 15 ml olive oil
- 100 g green garlic, trimmed and thinly sliced
- 300 g beet greens, washed, tough stems removed, roughly chopped
Custard & Cheese
- 4 eggs
- 240 ml whole milk, room temperature
- 120 g gruyère cheese, grated
- 30 g parmesan cheese, grated
- 5 g salt
- 2 g black pepper, freshly cracked
- 1 g ground nutmeg
Nutrition (per serving)
Nutrition is estimated per serving. Nutrients without complete source data are omitted.
Full nutrition
- Calories
- 327 kcal
- Protein
- 18 g
- Carbohydrates
- 31 g
- Fat
- 15 g
- Fiber
- 6 g
- Sugar
- 3 g
- Sodium
- 948 mg
- Saturated Fat
- 7 g
- Trans Fat
- 0 g
- Monounsaturated Fat
- 6 g
- Polyunsaturated Fat
- 2 g
- Cholesterol
- 153 mg
- Potassium
- 658 mg
- Calcium
- 425 mg
- Iron
- 3.0 mg
- Magnesium
- 78 mg
- Phosphorus
- 360 mg
- Zinc
- 2.4 mg
- Vitamin A
- 306 mcg
- Vitamin C
- 21 mg
- Vitamin D
- 1.3 mcg
- Vitamin E
- 1.6 mg
- Vitamin K
- 204 mcg
- Vitamin B6
- 0.4 mg
- Vitamin B12
- 0.9 mcg
- Thiamin
- 0.19 mg
- Riboflavin
- 0.46 mg
- Niacin
- 1.6 mg
- Folate
- 34 mcg
- Water
- 204 g
Sources: USDA FoodData Central
Method
In a medium saucepan, bring the vegetable broth to a boil over high heat. Stir in the pearl barley, reduce the heat to low, cover, and simmer for 30 minutes until the barley is tender and the liquid is fully absorbed.
Preheat the oven to 190°C (375°F) while the barley finishes cooking, and lightly grease a 2-liter baking dish.
In a large skillet, heat the olive oil over medium heat. Add the sliced green garlic and sauté for 3 to 4 minutes until softened and deeply fragrant, avoiding any browning.
Add the chopped beet greens to the skillet. Cook for 4 to 5 minutes, tossing continuously, until wilted and any excess moisture pooled at the bottom of the pan has entirely evaporated. Remove from heat.
In a mixing bowl, aggressively whisk together the eggs, whole milk, salt, black pepper, and ground nutmeg until completely smooth and homogenous.
Transfer the cooked barley and the wilted beet green mixture into the prepared baking dish. Add exactly half of the grated Gruyère and half of the Parmesan. Toss well to distribute the ingredients evenly.
Pour the seasoned egg custard over the barley and greens. Use a spatula to gently press the solids down so they are submerged. Sprinkle the remaining Gruyère and Parmesan over the top in an even layer.
Bake uncovered at 190°C (375°F) for 35 minutes. The edges should be bubbling and the cheese topping beautifully golden brown.
Remove from the oven and allow the gratin to rest for 10 minutes before slicing. This allows the custard to carryover cook and firm up, ensuring clean slices.
Chef's Notes
- Green garlic is immature garlic harvested in spring before the bulbs fully form. It has a milder, sweeter flavor than mature garlic cloves. If unavailable, substitute with 1 chopped leek and 1 clove of minced regular garlic.
- Beet greens are highly nutritious and taste strikingly similar to Swiss chard. Ensure you wash them thoroughly in a water bath to remove any hidden grit.
- For a nuttier texture, substitute the pearl barley with hulled barley, keeping in mind that hulled barley requires about 20 to 30 minutes of additional simmering time and more broth.
- Pre-cooking the barley in vegetable broth instead of water infuses the grain with foundational savory notes that elevate the entire dish.
Storage
Refrigerator: 4 days — Store in an airtight container once completely cooled.
Freezer: 1 month — Freeze in individual portions. Texture of the egg custard may change slightly upon thawing.
Reheating: Reheat in a 160°C/320°F oven until warmed through, or microwave loosely covered on medium power.
Troubleshooting
Watery consistency after baking
Cause: Beet greens released too much water and were not cooked down sufficiently before assembly
Fix: Return to the oven for an additional 10 to 15 minutes, or allow to rest longer at room temperature to absorb moisture
Prevention: Ensure all excess moisture is evaporated when sautéing the greens, pressing them in the skillet if necessary to release liquid
Barley is tough or chalky
Cause: Barley was not fully cooked before being added to the gratin
Fix: Cannot be fixed once baked into the custard
Prevention: Taste the barley at the end of the boiling phase; it must be completely tender before baking
Cultural Context
The gratin technique originated in French cuisine, traditionally involving a shallow baking dish and a perfectly browned crust of cheese or breadcrumbs. This modern, produce-driven adaptation marries the rustic, hearty nature of whole-grain barley with the ephemeral spring bounty of green garlic and beet greens, demonstrating a zero-waste approach by utilizing vegetable tops.
