Mix heavy cream, whole milk, sugar, espresso, and chocolate syrup in a bowl until sugar is dissolved. Refrigerate until chilled.
Pour the chilled mixture into an ice cream maker and freeze according to manufacturer's directions until it reaches "soft-serve" consistency. Stir in almonds and dark chocolate. Serve soft ice cream or transfer ice cream to a one- or two-quart lidded plastic container; cover surface with plastic wrap and seal. For best results, ice cream should ripen in the freezer for at least 2 hours or overnight.
