Root Vegetable and Whole Grain Mustard Gratin

the Breville Test Kitchen

Root Vegetable and Whole Grain Mustard Gratin

Name: Root Vegetable and Whole Grain Mustard Gratin
Cook time: 1200 s
Total time: 7200 s
Yield: Serves 8-10
Ingredients: 150 g Comte cheese; 100 g parmesan cheese; 4 cloves garlic - peeled; 1 red onion - peeled and halved; 600 g celery root - peeled and cut into large pieces; 600 g butternut squash - peeled and cut into large pieces; 600 g potatoes - peeled; 30 g unsalted butter; 2 tbsp yellow mustard seeds; 2 cups (480 ml) heavy cream - divided; 3 tbsp thyme leaves; 2 tbsp whole grain mustard; 2 tsp kosher salt; Finely ground white pepper - to season

The veggies are hard…but the slicing is not! The Breville Food Processor effortlessly produces thin, even slices for you to easily toss in the sauce and layer into the dish. A stint in the oven for everything to meld and mingle and your tender creamy cheesy gratin is ready.

the Breville Sous Chef® 9

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2 hrs total time

20 mins active time

Easy

Serves 8-10

Ingredients

Measurements:

150 g Comte cheese
100 g parmesan cheese
4 cloves garlic
peeled
1 red onion
peeled and halved
600 g celery root
peeled and cut into large pieces
600 g butternut squash
peeled and cut into large pieces
600 g potatoes
peeled
30 g unsalted butter
2 tbsp yellow mustard seeds
2 cups (480 ml) heavy cream
divided
3 tbsp thyme leaves
2 tbsp whole grain mustard
2 tsp kosher salt
Finely ground white pepper
to season

Instructions

1
Assemble the processor with the grey spindle and yellow reversible shredder, with the fine side up in the bowl and shred both cheeses. Remove and set aside.
2
Carefully assemble the clean processor bowl with the grey spindle and green S-blade™. Add the garlic and process until finely chopped, scraping down the side occasionally. Carefully remove the S-blade™ leaving the garlic in the bowl.
3
Assemble the processor with the grey spindle and orange adjustable slicer set on 2 in the bowl and slice the onion. Remove and set aside.
4
With the process still set up with the slicer set on 2, slice the celery root and transfer to a large mixing bowl. Slice the squash and then the potatoes and transfer to the mixing bowl. Mix the vegetables to distribute evenly.
5
Melt the butter in a large frying pan over medium-high heat. Add the garlic and onion and mustard seeds and saute for 4 minutes, or until softened. Add 1½ cups (360ml) cream and thyme and bring to a boil. Reduce the heat and simmer for 2 minutes to infuse. Add the whole grain mustard, salt and pepper and stir to combine.
6
To preheat the oven, insert the wire rack into position 6. Set the oven to Bake, Convection, 165°C, Rotate Remind, for 1 hour 15 minutes and press Start. Meanwhile, continue to the next step.
Tip: Recipe has been optimized for the Smart Oven Air Fryer Pro.
7
Pour the hot cream over the vegetables. Add the remaining ½ cup (120ml) cream and mix to coat. Place half the vegetables in a 28cm x 23cm baking dish and flatten. Sprinkle over half the cheese and repeat with the remaining vegetables and cheese. Cover with foil.
8
Once preheated, place in the oven and bake for 1 hour 15 minutes. When the Rotate Remind signals, remove the foil and continue baking until golden brown and the vegetables are tender when tested with the tip of a knife.
9
Remove from the oven and allow to stand for 10 minutes before serving. Serve sprinkled with finely chopped parsley, if desired.