Whisk together the sugar and cornstarch in a medium saucepan until well blended and no lumps of cornstarch remain. Slowly drizzle in the milk, whisking until smooth, then whisk in the eggs.
Cook the pudding over medium heat until it begins to thicken, about 5 minutes, whisking often. Reduce heat to medium-low and, using a rubber spatula, stir the pudding, scraping the sides and bottom of the pot until thickened, about 3 more minutes.
Off heat, whisk in the almond butter and vanilla. Transfer pudding to a bowl, cover with plastic wrap, pressing it to the surface to prevent a skin from forming, and chill the pudding for at least 2 hours (can be made a day in advance).
To assemble parfaits, spoon 1/3 cup of the chilled pudding into each of four parfait glasses. Top with some of the berries and 2 tablespoons cereal, then layer another 1/3 cup pudding on top, followed by more berries and cereal.
240 calories;12 g fat; 3 g saturated fat; 330 mg cholesterol; 11 g protein; 22 g carbohydrates; 1 g fiber;
30 mg sodium; 200 mg calcium (20% of daily value). Nutrition figures based on using fat free milk.