Prepare the apple filling for the strudel. Cut the apples into thin slices. Pour boiling water over the raisins and leave for 10 minutes, then drain and dry it. Then melt a little butter (70 g) in a medium-sized frying pan over medium-high heat (we will use the rest of the butter later). Add sugar to the butter and melt it. Spread the apples with the melted mass, add cinnamon. Simmer for 5-7 minutes without covering (we need to evaporate the liquid), stirring occasionally. Then add the raisins and nuts and simmer until the moisture evaporates, about 3-5 minutes. Transfer the finished filling to another bowl and let cool completely.