Spread almond slivers out in a single layer on a rimmed baking sheet. Toast in a 350°F oven for 5-10 minutes, until nicely browned. OR toast in stick-free or cast-iron skillet on medium high, stirring frequently until browned. Set aside.
Combine cabbage, pak choi, peas, radishes, green onions, cilantro in a large bowl. Can make this step a day or two ahead.
In a separate bowl, mix together the rice vinegar, sugar, soy sauce, garlic, sesame oil, ginger, and cayenne until sugar has dissolved. Whisk in the mayonnaise.
When ready to serve, gently combine the dressing and almonds with the