Prep the plums. Wash, pit, and thinly slice or dice the plums. Toss with lemon juice and a tiny pinch of salt if using.
Let them sit for 2–3 minutes while you get everything else ready.
Sweeten the yogurt (optional). In a bowl, stir the yogurt with honey or maple syrup and vanilla. Taste and adjust sweetness. Keep it lightly sweet so the fruit stands out.
Toast your crunch. If you’re using plain oats or nuts, lightly toast them in a dry skillet over medium heat for 2–3 minutes until fragrant.
This adds depth and keeps the parfait from tasting flat.
Layer the base. Spoon a few tablespoons of yogurt into the bottom of a glass or bowl. Add a layer of plums, then a sprinkle of granola, nuts, and seeds.
Repeat the layers. Continue layering yogurt, plums, and crunch until you reach the top. Finish with a few plum slices, a dusting of cinnamon or cardamom, and mint if you like.
Serve right away. Enjoy immediately for the best texture, or chill for up to 30 minutes if you like it extra cold.