Frozen Walnut Cinnamon Mousse

This is a delicious and quite healthy desert, perfect for hot summer days. Despite its simplicity (6 ingredients), it is a sophisticated dish that is likely to impress. The recipe uses flavors from the Slovenian region of Prekmurje, where walnuts, honey, dairy, and buckwheat commonly appear in regional cuisine.

The buckwheat flour, and perhaps the honey, are a bit unusual, but do try to use them if you can. They combine to give a really cool flavor! If nothing else, do your best to use honey instead of sugar.

• Walnuts - about 11 oz (300 g) shelled
• Milk - 3/4 quart (750 ml)
• Cinnamon stick
• 1 egg (not shown)
• Honey (strongly recommended) or sugar - a few tablespoons
• Buckwheat (recommended) or white flour - a few tablespoons
• Mint (for serving)

Heat the cinnamon stick in the milk on low heat so that the cinnamon flavor infuses the milk. Do not let the milk boil during this stage, which should take about 10 minutes. If you don't have a cinnamon stick, don't worry. Just use half a teaspoon of cinnamon instead, or to taste.

Meanwhile, prepare the walnuts. If using whole walnuts, shell them. Leave one quarter of the shelled walnuts in large pieces for texture; chop or mash the rest into small pieces (see picture). The small pieces help thicken the mousse.

Add the walnuts to the simmering milk. Keep the mixture at a gentle simmer for the duration of the cooking period; the milk should not boil vigorously.

When the walnut pieces begin to soften (20 minutes or so), prepare the egg. Separate the yolk and white. Add the yolk and then beat the egg white until stiff; fold it in separately. This makes the final product airier. If you don't want to go to the trouble, no problem. You could just mix in the unseparated egg and still get a great result.

Next, add a tablespoon or two of flour. This is not traditional for a mousse, but a bit of flour helps the final product stick together, and if using buckwheat flour, adds an extra dimension of flavor. If you are using sugar, add it now as well. Wait if you are using honey.

Continue simmering on low heat for another half-hour or so, stirring periodically. The mixture should take on the consistency of a thick pudding. If necessary, use extra milk or flour to adjust consistency. When ready to come off the stove, the mousse will have noticeably thickened, the walnuts and milk will have incorporated, any walnut pieces will be soft, and the color will have become browner. Turn off the heat. If using honey, add it now and mix to incorporate. Adding it now preserves delicate flavors and enzymes that would be destroyed by prolonged exposure to heat.

For reference, compare pictures 1 (walnuts just added), 2 (just after adding flour), and 3 (done). Notice how the mixture is the most uniform and brownest in picture 3 (bottom right).

Let the mousse cool to room temperature. When cool, remove the cinnamon stick. Pour the mixture into a container and freeze.

Before serving, place the mousse in the fridge for an hour or so. The mousse should be slightly thawed; it is much better if not frozen solid. If you can cut it without extreme effort, it is ready. Cut into slices and serve. A sprig of mint, if you have it, does wonders for the final result.