Heat oven to 325°F. Put hazelnuts on a baking sheet and roast for 10 to 15 minutes, until skins darken and crack. Put roasted nuts in a clean towel and rub off skins. Discard skins and let nuts cool.
In a food processor, grind nuts with half the rice flour until mixture resembles coarse cornmeal. Add remaining rice flour and salt and pulse briefly.
Cream sugar and butter in a mixing bowl with a wooden spoon for a minute or two until pale and thick. Add nut mixture and combine until dough comes together. If it seems crumbly, add 1 to 2 tablespoons softened butter or a little cold water.
Press dough evenly into a 10-inch tart pan; use half the dough for the sides and half for the bottom. Prick bottom with a fork and freeze for 30 minutes (or several days if desired).
Heat oven to 350°F. Bake chilled tart shell about 15 minutes until lightly brown. Cool.