Instructions

Creamy gratin

1. Preheat the oven to 350°F (175°C).
2. Peel and slice the root vegetables thinly. Heat the heavy cream in a saucepan, press in the garlic. Salt and pepper.
3. Lower the heat and add the vegetables. Let simmer for 10 minutes on medium-high heat. Stir in the shredded parmesan, save some for the gratinating. Distribute into ramekins and top with the rest of the parmesan cheese.
4. Bake in the oven for 20 minutes while you prepare the meat and the butter. You can also prepare the gratin the day before and just heat up when serving. Raise the heat or turn on the grill function towards the end for a nice golden result.

Tarragon butter

1. Melt one-third of the butter on medium heat until it turns amber in color and smells nutty. Set aside and allow to cool slightly.
2. Add tarragon, vinegar, onion powder, salt and pepper.
3. Whisk the remaining butter into the melted butter and keep whipping with a hand mixer until fluffy.
4. Keep in the refrigerator but bring to room temperature 15 minutes before serving.

Beef sirloin

1. Pat the meat dry with a kitchen towel. Rub with salt and pepper on both sides.
2. Put in a greased oven dish. Insert a meat thermometer in the thickest part. Roast in the middle of the oven until the inner temperature reaches 130°F (54°C), it takes about 30 minutes.
3. Remove from the oven and allow rest for a few minutes. Cut into slices. Serve with leafy greens, some tarragon butter and the creamy gratin.