Raspberry Swirl Rolls

In small saucepan, heat milk and 1/2 cup water on medium-low until warm but not hot to the touch. Meanwhile, in large bowl, whisk together yeast, granulated sugar and 1 cup flour. Stir in warm milk. Cover and set aside until thick and foamy, about 15 minutes. Mix in melted butter and salt. Gradually mix in remaining 2 cups flour. Cover and let rise until doubled in size, about 1 hour.  Meanwhile, lightly coat 11" by 8" casserole dish with oil. Line pan with parchment paper, leaving 3-inch overhang on 2 long sides; oil parchment. In small bowl, combine jam, lemon zest and 1 tablespoon lemon juice. Turn dough out onto floured surface. Roll into 12" by 9" rectangle. Spread with jam mixture and top with raspberries. Starting from long side, roll dough into tight log, pinching seam to seal.  Slide long piece of unflavored dental floss under log of dough about 1 inch from end. Holding floss taut, lift ends and cross to cut off 1 piece dough. Repeat to cut 12 1-inch-thick rolls. Transfer rolls, cut sides up, to prepared pan, spacing equally. Cover and let rise until rolls have doubled in size and are touching, 50 to 60 minutes. Meanwhile, heat oven to 375°F. Brush rolls with heavy cream and bake until puffed and light golden brown, 25 to 27 minutes. Let cool on wire rack 10 minutes. Make frosting: In medium bowl, combine sour cream, confectioners’ sugar, vanilla and remaining 1 tablespoon lemon juice. Spread over warm rolls.