1. Preheat oven to 360 F. 2. Melt butter. 3. Wrap the bottom and outer sides of the springform with aluminum foil to prevent leakage. Butter inner side of the springform with melted butter. 4. Grate zest of one lemon. 5. In a large bowl: combine ricotta, cream cheese, sour cream, sugar, and eggs. Mix about 2 min on slow-medium speed of mixer or using spatula. We need just combine a little bit all this ingredients. Add flour and lemon zest. Mix 1 min. Add vanilla extract and remaining. Mix well and beat 20 minutes on medium-high speed. 6. Pour cheesecake mixture into springform. Bake 1 hour or until light golden-brown color on medium level of the oven. Check cheesecake thru the oven window. Do not open the oven! 7. Turn off the oven. Do not open the oven. Let cheesecake slowly cool in the oven. About 2 hours. 8. Using a knife, gently run around the edge of the cheesecake to make easier to remove the side of the springform. 9. Place the cheesecake to the refrigerator overnight, or minimum on 4 hours. SERVING IDEAS: - Spread or drizzle lingonberry jam (as o a picture) or any you favorite jam over the top just before serving. - Add a light dusting of powdered sugar for a simple, elegant finish. - Serve with fresh berries for extra freshness and color. - Pair with a cup of coffee or tea for a classic dessert experience. - Add a dollop of whipped cream for a more indulgent presentation. - Garnish with thin lemon zest strips to highlight the citrus notes.

   1. Sift 350 g of all-purpose flour into a large bowl. Make a well in the center; put yeast and sugar to a middle of this well; add lukewarm milk. Cover and leave this starter to rise for 30 minutes. 2. Add the remaining sugar and milk, pieces of soft butter, eggs, rum, salt and lemon zest to the starter. Knead everything thoroughly with a mixer until bubbles appear and the dough comes away easily from the walls of the bowl. Sift the remaining flour into the same bowl and knead the dough again. Cover and leave to rise for 30-40 minutes. 3.Roll out the dough on a floured surface (thickness 0.7-1 cm). Using a cup, lightly squeeze out circles with a diameter of about 8 cm on one half of the cake. Place 1 teaspoon of the marmalade or jam in the middle of each circle. Press the dough around the filling. Using a mug, cut out rounds and place on a lightly floured surface. Cover with a kitchen towel and leave to rise for 30 minutes. 4. Heat oil in a tall frying pan or saucepan. If the oil has reached the desired temperature, bubbles will appear on a wooden spoon dropped into it. Reduce heat (middle level). 5. Place donuts in portions in oil and fry on both sides. Sprinkle the tops of the finished donuts with powdered sugar.