1 package yeast or 1 1/2 tsp. yeast
1 cup warm milk
4 cups flour
3/4 cup butter or margarine, softened
6 Tbs. sugar
1 tsp. salt
1 egg yolk
1 Tbs. grated lemon zest
1/2 cup fresh lemon juice
1 Tbs. cornstarch
6 Tbs. butter
3/4 cup white sugar
4 egg yolks, beaten
In medium saucepan, mix together 1 tablespoon lemon zest, 1/2 cup lemon juice and 1 tablespoon cornstarch until smooth. Mix in 6 tablespoons butter and 3/4 cup sugar, and bring mixture to boil over medium heat. Boil for one minute, stirring constantly. In small bowl, with a wire whisk, beat egg yolks until smooth. Whisk in a small amount of the hot lemon mixture. Pour the egg mixture into the sauce pan, beating the hot lemon mixture rapidly. Reduce heat to low; cook, stirring
constantly, 5 minutes, or until thick (not to boil).
Pour mixture into medium bowl. Press plastic wrap onto surface to keep skin from forming as it cools. Cool to room temperature. Refrigerate 3 hours.
Dissolve the yeast in warm milk. Add 1 3/4 cups flour and mix thoroughly. Cover bowl with plastic wrap and allow mixture to rise 45 minutes.
Place butter, sugar and salt into a bowl and mix them together. Add eggs and one egg yolk, one at a time, beating well after each egg is added.
Add 1 3/4 cups flour and mix until well blended. Add sponge and mix well. Add remaining flour and knead .
Place dough in a large oiled bowl and turn the dough once. Let rest until double in size.
Punch dough down. Cover bowl with plastic wrap and refrigerate at least 4 hours or over night.
Remove a portion of the dough and roll on a floured surface to about a 1/4 of an inch thick. Using a large (about 5 inch diameter)
biscuit cutter or circle, cut as many brioche circles as possible.
Place 1 1/2 Tablespoons of lemon filling in the middle of each brioche circle. Fold the outsides of the circle in and pinch in the middle. Place each one so pinched surface is on the bottom in greased 3 inch small tart pan (You will need about 12-14.) Cover; let rise at room temperature, until doubled in size.
Beat 2 eggs in a small bowl. Using a pastry brush, lightly brush tops of lemon brioche with the egg. Sprinkle with sanding sugar crystals.
Bake at 350 degrees for 10-12 minutes. Remove from pans when cool.