• Clean and cut the tuna steak into small cubes.
• Crush finely some tigernuts and fry them a little in a well warm frying pan.
• Add to the tuna the crushed tigernuts, a few drops of lemon, salt and extra virgin olive. Let marinate a little.
• To do the air of horchata it is necessary to put to soaking a few raw tigernuts during 24 h. (1 l. of water for every 200 gr. of groundnuts). Crush the tigernuts with the water in the Thermomix and drain the milk with help of a thin rag.
  
• Add to this milk a soup spoonful of lecitin of soya in dust, and warm to 40ºC approximately. Crush up to obtaining a light froth.

To assemble the dish:

• Arrange in the bottom of a cocktail glass, the tuna dressed with salt and  sheets of toasted almonds, and cover up to the rim with the horchata fam.
  
  The Tuna Tartar with air of horchata is a creation of Bernd Knöller, chef of the Restaurant Riff.