Bernaise Onion Tart

Preheat oven to 350 degrees.

• Flaky pastry for a 10” tart or deep-dish pie plate.

• 3 T butter
• 2 1/2 lb onions, thinly sliced
• 1/4 c unbleached all-purpose flour
• 1/2 t salt
• 1/8 t nutmeg
• 1 t ground mustard
• 2/3 c milk
• 3 eggs
• 1 c sour cream
• 2 c (8 oz) Swiss, Greyere or Emmenthaler cheese, grated (I use Jarlsberg Swiss.)
• Salt to taste

Melt butter in a 3-4-quart straight-sided saute pan over medium heat.

Add onions and cook, covered, stirring often, until soft (10-15 min).

Uncover and continue cooking, stirring often, until lightly brown (12-15 min). (Do cook this long!)

Stir in flour, salt, nutmeg and mustard.

Remove from heat and slowly stir in milk.

Return to heat and bring to a low boil, stirring, and continue to stir and simmer the sauce until thickened.

Beat eggs in a large bowl, then stir in sour cream and cheese.

Stir onion mixture into the egg-sour cream mixture; check seasoning for salt.

Pour into prepared pastry.

Bake on the bottom rack for 50-55 minutes or until crust is browned and filling is firm when gently shaken.

Let cool on a rack a few minutes before serving.

Serves 8.