Cauliflower, Red Onion, and Chestnut Tart

INGREDIENTS

rectangle Hazelnut Pastry Dough

All-purpose flour, for surface

4 oz

red pearl onions

small head cauliflower, separated into florets

Coarse salt

2 tsp

extra-virgin olive oil

2 tbsp

unsalted butter

2 tbsp

all-purpose flour

1 cup

whole milk

1/2 cup

crumbled blue cheese (2 ounces)

1 tsp

chopped fresh thyme

Coarse salt

1/3 cup

coarsely chopped chestnuts