Peel four large cucumbers and cut in thin slices. Put in saucepan with one cup cold water, bring to boiling-point, and cook slowly until soft; then force through a purée strainer. Add two and one-half tablespoons granulated gelatine dissolved in three-fourths cup boiling water, few drops onion juice, one tablespoon vinegar, few grains cayenne, and salt and pepper to taste. Color with leaf green, strain through cheese-cloth, and mould same as Fruit Chartreuse . After removing small mould fill space with Tomato Mayonnaise. Garnish sides of mould with thin slices of cucumber shaped with a small round fluted cutter, and on the centre of each slice place a circular piece of truffle. Garnish around base of mould with small tomatoes peeled, chilled, and cut in halves crosswise. On each slice of tomato place a circular fluted slice of cucumber, and over all a circular piece of truffle. Serve with.
Tomato Mayonnaise. Color mayonnaise red with tomato purée.