1. Wash pot with soap and water and dry well. Line pot with cooking parchment: Push center of parchment into pot, then press outward to fit contours of pot; bend parchment edges outward over edges of pot.
2. In a bowl, with a mixer on high speed, beat butter and sugar until fluffy. Add eggs and beat until well blended. Turn mixer to medium and beat in sour cream.
3. In another bowl, mix flour, raisins, baking powder, baking soda, and cardamom. Add to butter mixture and beat on medium speed until well blended. Scrape batter into parchment-lined pot. Sprinkle almonds evenly over the top.
4. Set cake in the lower third (but preferably not on bottom level) of a 300° regular or convection oven. If you must set pot on the bottom level to fit, place on an inverted shallow baking pan to lift cake slightly so bottom doesn't get too brown. If parchment touches top of oven, fold down farther over pot edges. Bake until a long wooden skewer inserted in center of cake comes out clean, 1 1/2 to 1 3/4 hours.
5. Cool cake in pot on a rack for 15 to 20 minutes, then lift from pot and set upright on rack. Cool at least 1 1/2 hours longer. For presentation, return cake to pot. To serve, lift cake from pot, peel off parchment, and cut into wedges.