Step 1In a medium, heavy-bottom saucepan, bring the water, sugar, rose hip tea and cardamom to a gentle simmer and cook slowly until the sugar is dissolved and the rose hips have softened, 12 to 15 minutes.
Step 2Increase the heat to medium and bring the mixture just to a boil. Remove from heat and stir in the lemon juice and rose water. Set aside to cool while the doughnuts are made, then strain before using. If not using immediately, cover and refrigerate until needed.
Step 1In a medium bowl, combine the flour, cardamom, cinnamon and salt. Set aside.
Step 2In a medium, heavy-bottom pot, combine the water, sugar and butter. Bring to a boil over high heat, making sure the butter is fully melted.
Step 3As soon as the water is boiling and the butter is melted, add the flour mixture all at once. Remove the pan from the heat and stir the mixture vigorously with a wooden spoon until the dough comes together in one lump, 1 1/2 to 2 minutes. Add the egg yolks, one at a time, into the mixture, stirring constantly. Be sure that the first yolk is almost entirely absorbed before adding the second yolk. The dough should be light and soft, but stiff enough to form into a doughnut shape; if the dough is overly stiff, add egg white a little at a time until the desired consistency is achieved. Stir constantly until the mix comes together as a glossy dough, 4 to 6 minutes.
Step 4Dampen your hands with cold water and divide the dough into 8 even pieces. Roll each piece into a ball (wet your hands if the dough begins to stick). On a firm work surface, punch a hole through the center of each ball with your finger. Widen the hole slightly with your finger to form a doughnut. Continue with each ball of dough.
Step 5Fill a deep pot with oil to a depth of about 3 inches. Heat the oil until it shimmers and reaches 350 degrees on a thermometer.
Step 6Drop the doughnuts, a few at a time, into the oil and fry until the outside of each is golden and the center is cooked through and not doughy, 7 to 10 minutes; they will be soft, almost pillowy, in texture. Strain the doughnuts, draining any excess oil, then immediately dunk them into the rose hip syrup.
Step 7Drain and serve the doughnuts with sour cream or yogurt, berries and jam on the side and with a little syrup drizzled over the doughnuts.