Bring 4 quarts of salted water with the added potato to a boil. Make sure to salt the water a little less than you normally would when boiling pasta, and ignore the fact that the potato will also absorb part of the already reduced amount. When the water is boiling, add the pasta. Boil as usual, noting the recommended time on the package, until the pasta is just al dente.
Preheat the oven to 300 F. Mix the canola oil, the water and honey in a jug and microwave on medium heat for 20 seconds. In a mixing bowl mix the rye flakes with the spices and a pinch of salt and drizzle over the honey mixture, stirring to coat the flakes evenly. Spread them on a rimmed baking sheet lined with parchment paper and bake in the preheated oven, stirring every 5 minutes, until crispy. Keep a close eye on them, they can burn easily if distracted with the other steps in the recipe.
Remove the two potato halves from the pasta water to a blender. Drain the pasta and add back in half of the milk, warmed up, and put back on the burner over medium heat. Meanwhile blend the potato, one apple, peeled , cored and quartered, and the rest of the milk until smooth.
Add the milk mixture to the pasta along with the grated cheese and cream stirring slowly and steadily until all is smooth and blended. By then the pasta should be cooked just right. Remove the pot from the heat.
Peel and chop 4 of the apples into ½ inch cubes. Melt the ¼ cup of butter into a large sauté pan or a skillet and add the apple cubes in a single layer. If your skillet is not wide enough, do this in two separate 2 Tablespoons of butter-2 apples portions. Saute the apples , shaking the pan only occasionally until golden on the outside, add the 1 ½ tsp of sugar and quickly caramelize them over high heat.
Laddle some of the pasta into a pasta bowl. Add some of the sautéed apples , barely stirring them in and top with a generous amount of rye flakes. Serve along with extra milk.