Russian Tea Biscuits

Mix dry ingredients (flour, baking powder, salt, sugar) in a large bowl. In another bowl, mix oil, melted butter, orange juice and rind, vanilla, and eggs (4 yolks, 3 whites). Knead dough and refrigerate 2 hours or overnight. Mix cinnamon and sugar. Split dough into 4 equal pieces. Roll each piece on a floured surface into a rectangle approximately 7 inches by 10 inches (just smaller than a piece of typing paper). Spread jam across all but a half-inch strip along one of the short sides. Sprinkle 1/3 cup walnuts and 1/2 cup raisins over dough, again leaving a half-inch strip. Roll up jelly-roll side from the other short side, using the empty strip to seal the roll. Brush top with reservered egg white, and sprinkle with cinnamon-sugar mixture. Repeat for other 3 piece of dough. Cut each roll into four slices, and place on lightly-greased (or parchment-papered) jelly-roll pan or baking sheet. (Use a pan with sides, since some jam may drip.) Bake in a 350 degree oven for 25-35 minutes, until tops are nicely golden. Variations: Use other types of jam, nuts, and dried fruit. Use white or colored decorator's sugar in place of cinnamon-sugar mixture for a different look. Roll smaller for cookie-sized biscuits (reduce cooking time and watch carefully).