Preparation Bring cream and 1/2 cup sugar just to a boil in a 2- to 4-quart heavy saucepan, stirring until sugar is dissolved. Remove from heat and keep hot, covered. Beat together yolks, salt, and 3 tablespoons sugar in a large bowl with an electric mixer at high speed until tripled in volume and thick enough to form a ribbon that takes 2 seconds to dissolve into mixture when beater is lifted, 3 to 4 minutes in a stand mixer or 4 to 8 with a handheld. Reduce mixer speed to low and add hot cream mixture to yolks in a slow stream, then transfer custard back to saucepan. Cook over moderately low heat, stirring constantly with a wooden spoon, until custard is slightly thickened and registers 170°F on thermometer (do not let boil). Pour custard through a fine-mesh sieve into a large heatproof bowl, discarding solids. Let custard cool to room temperature, stirring occasionally. While custard cools, combine cranberries, remaining cup sugar, and cinnamon stick in a 2-quart heavy saucepan and bring to a boil over moderately high heat, stirring. Reduce heat to low and simmer, covered, stirring occasionally, until cranberries have burst, about 10 minutes. Remove and discard cinnamon stick, then carefully transfer cranberry mixture to a blender and purée until smooth (use caution when blending hot mixtures). Force through fine-mesh sieve into bowl of custard, pressing on solids with back of a spoon and then discarding them. Cool to room temperature, stirring occasionally, about 45 minutes. Freeze custard in ice cream maker. Transfer to an airtight container and put in freezer to harden, at least 4 hours.
Preparation Bring cream and 1/2 cup sugar just to a boil in a 2- to 4-quart heavy saucepan, stirring until sugar is dissolved. Remove from heat and keep hot, covered. Beat together yolks, salt, and 3 tablespoons sugar in a large bowl with an electric mixer at high speed until tripled in volume and thick enough to form a ribbon that takes 2 seconds to dissolve into mixture when beater is lifted, 3 to 4 minutes in a stand mixer or 4 to 8 with a handheld. Reduce mixer speed to low and add hot cream mixture to yolks in a slow stream, then transfer custard back to saucepan. Cook over moderately low heat, stirring constantly with a wooden spoon, until custard is slightly thickened and registers 170°F on thermometer (do not let boil). Pour custard through a fine-mesh sieve into a large heatproof bowl, discarding solids. Let custard cool to room temperature, stirring occasionally. While custard cools, combine cranberries, remaining cup sugar, and cinnamon stick in a 2-quart heavy saucepan and bring to a boil over moderately high heat, stirring. Reduce heat to low and simmer, covered, stirring occasionally, until cranberries have burst, about 10 minutes. Remove and discard cinnamon stick, then carefully transfer cranberry mixture to a blender and purée until smooth (use caution when blending hot mixtures). Force through fine-mesh sieve into bowl of custard, pressing on solids with back of a spoon and then discarding them. Cool to room temperature, stirring occasionally, about 45 minutes. Freeze custard in ice cream maker. Transfer to an airtight container and put in freezer to harden, at least 4 hours.