How to Make It
Set a medium bowl in a large bowl of ice water. In another medium bowl, beat the egg yolks until pale, 1 to 2 minutes.
In a medium saucepan, whisk the cream with the milk, sugar, salt and the vanilla bean and seeds. Bring to a simmer, whisking, until the sugar is completely dissolved. Very gradually whisk half of the hot cream mixture into the beaten egg yolks in a thin stream, then whisk this mixture into the saucepan. Cook over moderately low heat, stirring constantly with a wooden spoon, until the custard is thick enough to lightly coat the back of the spoon, about 12 minutes; don’t let it boil.
Strain the custard through a medium-mesh strainer into the bowl set in the ice water; discard the vanilla bean. Let the custard cool completely, stirring occasionally. Stir in the almond extract. Pour into a large resealable freezer bag and seal, pressing out the air. Lay the bag flat in the freezer and freeze until firm, at least 8 hours or overnight.
Working quickly, in batches if necessary, transfer the frozen custard to the bowl of a food processor. Pulse at 5-second intervals until smooth. Transfer the custard to a chilled 9-by-4-inch metal loaf pan and fold in the cherries and pistachios. Cover with plastic wrap and freeze until firm, about 6 hours or overnight.
Instead of cherries and pistachios, try folding in 1 cup of chopped chocolate-covered pretzels or chopped halvah.