Pourable Maple Yogurt with Apple and Walnuts

Steps

1. Wash a heavy pot, whisk, thermometer and a 1.5-quart jar with hot soapy water, then rinse with boiling water to sanitize.
2. Pour the commercially pasteurized 2% milk into the pot and heat over medium-low, stirring often, to 180°F (82°C). Hold between 180°F and 185°F (82–85°C) for 10 minutes, stirring so it doesn't scorch; this makes a thinner, pourable yogurt than a longer hold.
3. Take the pot off the heat and cool the milk to 108–112°F (42–44°C), setting the pot in a sink of cold water to speed it up, stirring and checking with the thermometer.
4. In a small bowl, whisk the plain yogurt with a ladle of the warm milk until smooth, then stir this starter mixture back into the pot.
5. Pour into the sanitized jar, cover, and incubate at 108–112°F (42–44°C) for 6 hours (oven with the light on, a cooler with warm water, or a yogurt maker) until softly set and tangy.
6. Refrigerate the yogurt right away at 40°F (4°C) or below for at least 4 hours until cold. Whisk it well to make it smooth and pourable; yield is about 1 kg, nothing drained.
7. While it chills, toast the walnuts in a dry skillet over medium heat for 3–4 minutes until fragrant, then cool.
8. Toss the apple with the lemon juice so it stays bright.
9. Whisk the maple syrup and ground ginger into the chilled yogurt.
10. Pour the maple yogurt into 4 glasses or bowls and top with the apple and toasted walnuts. Keep leftovers refrigerated up to 1 week.