Whisk together the mustard and vinegar in a large bowl. Drizzle in the olive oil, whisking until the dressing is emulsified. Season with 1/4 teaspoon salt.
Cook the chicken strips according to the package directions, set aside. Using a knife or mandoline, thinly slice the apple into half-moons. Add the apples to the dressing and toss to coat. Add the chicken, arugula, smoked almonds and 1/4 teaspoon salt; toss to coat. Dollop the ricotta over the top and serve immediately.