Arrange a steamer basket in a medium pot and add enough water to just reach the bottom of the basket.

Bring to a boil, add beets to steamer basket, cover, reduce heat and simmer until beets are tender, about 1 hour.

Remove steamer basket from pot, set aside until beets are cool enough to handle, then thinly slice.

Heat oven to 250ºF. Arrange walnuts on a large plate.

Dredge each round of chèvre in the walnuts, patting lightly to make sure that the walnuts adhere all over.

Transfer to a parchment paper-lined baking sheet and bake until chèvre is just warm throughout but still holds its shape, about 10 minutes.

Meanwhile, heat oil in a large skillet over medium heat.

Add garlic and cook, stirring often, until just golden, about 30 seconds.

Whisk in vinegar then add sliced beets, salt and pepper and cook, stirring often, until beets are just heated through, about 1 minute.

Arrange field greens on four large plates.

Using a slotted spoon, divide beets between plates, spooning them over the greens.

Drizzle with remaining dressing in skillet and top with warm chèvre. Serve immediately.