Courgette and potato gratin with the Thermomix® works without pre-salting the courgettes. We slice both vegetables to 5 mm, layer them alternately and let the courgette moisture evaporate during the 50-minute baking time. The cream sauce takes the Thermomix® just 5 minutes to prepare.
Most gratin recipes say: salt the courgettes, leave for 30 minutes, pat dry. We skip that step. The reason: at 5 mm thickness and 50 minutes at 180°C top and bottom heat, the courgette moisture evaporates on its own. The gratin does not turn watery. Instead, the slices hold their shape and the cheese absorbs the remaining moisture.
Courgette and Potato Gratin (Thermomix®)
Ingredients 0 / 12 ✓
- 700 g waxy potatoes
- 500 g courgettes
- 200 g Gouda
- 2 garlic cloves
- 1 onion
- 20 g butter + a little extra for greasing
- 2 sprigs marjoram
- 400 g double cream
- 2 pinches freshly grated nutmeg
- 1 tsp salt
- some freshly ground pepper
- 1/2 bunch chives
Instructions 0 / 12
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1
Wash and peel the potatoes, wash the courgettes. Slice both into rounds approximately 5 mm thick.
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2
Preheat the oven to 180°C top and bottom heat. Grease the baking dish.
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3
Layer the potatoes and courgettes in the baking dish.
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4
Cut the cheese into pieces, place in the mixing bowl and chop for 10 sec / speed 8, then set aside.
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5
Peel the garlic, place in the mixing bowl and chop for 3 sec / speed 8.
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6
Peel the onion, halve it, place in the mixing bowl and chop for 5 sec / speed 5, then scrape down with the spatula.
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7
Add the butter and sweat for 3 min / Varoma / speed 2.
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8
Meanwhile, wash the marjoram, shake dry and pick off the leaves.
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9
Add the marjoram, double cream, nutmeg, salt, pepper and 100 g Gouda and bring to the boil for 5 min / 100°C / speed 4, then pour evenly over the gratin.
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10
Scatter the remaining cheese over the gratin and bake on the middle shelf for about 50 minutes.
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11
Meanwhile, wash the chives, shake dry and cut into small rings.
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12
Serve the gratin scattered with chives.
Tip: If the gratin starts to brown too quickly during baking, cover it with a piece of aluminium foil to prevent the top from burning while the potatoes finish cooking.
Video
Nutrition per serving
5 mm slice thickness for both vegetables
Slice the potatoes and courgettes to exactly 5 mm. Thinner and the slices fall apart; thicker and the potatoes will still be hard after 50 minutes. Waxy potatoes (such as Charlotte or Nicola) are essential here because they hold their structure. Floury potatoes would break down during baking and turn into a mushy mass.
Wash the courgettes but do not peel them. The skin stabilises the slices during baking and stops them from becoming too soft.
Cream sauce with marjoram instead of thyme
The cream sauce cooks in the Thermomix® in 5 minutes. Garlic and onion are sweated in butter first (3 minutes Varoma speed 2), then double cream, nutmeg, salt, pepper and 100 g of the Gouda are added. Everything is brought to the boil at 100°C speed 4. The remaining 100 g of cheese is scattered over the gratin later.
Marjoram is not just an interchangeable herb garnish here. It has a slightly bitter, savoury flavour that balances the natural sweetness of the courgettes. Thyme would be too dominant and would overpower the vegetables. Two sprigs of marjoram are enough; the leaves go straight into the cream.
Layering and baking time
Layer the potatoes and courgettes alternately in the greased baking dish. No strict order is needed. Just mix them through so that every portion gets both vegetables. Spread the cream sauce evenly over the layers and add the remaining cheese as the final layer on top.
The gratin bakes for 50 minutes on the middle shelf at 180°C top and bottom heat. After 40 minutes, check whether the cheese on top is already browning. If so, cover the gratin with aluminium foil to prevent the crust from burning while the potatoes finish cooking.
Testing doneness with a knife
After 50 minutes, insert a knife into the centre of the gratin. If the potato slices are tender and the knife slides through without resistance, the gratin is ready. If the potatoes are still firm, give it another 10 minutes. The courgettes will always be soft enough by this point.
Add chives after baking
Cut the chives into small rings and scatter them directly over the finished gratin just before serving. During baking they would burn and turn bitter. The fresh green rings give the gratin a visual contrast to the golden cheese crust and add a mild onion flavour.
Storing leftovers in the fridge
Goes well with: schnitzel and baguette.
The gratin keeps for 3 days in the fridge when covered. To reheat, cover and place in the oven at 160°C for 20 minutes. The cheese crust turns rubbery in the microwave, so the oven is the better option. Freezing does not work well because the courgettes become mushy and release water when thawed.
More Thermomix® oven dishes: Gratins and bakes with the Thermomix®
