In large serving bowl, add the kale, half of lemon juice, a drizzle of oil and a little salt. Massage until the kale starts to soften and wilt, 2 to 3 minutes. Set aside while you make the dressing.
In a small bowl, whisk remaining lemon juice with the honey and lots of black pepper. Gradually add the ¼ cup of oil while whisking until a dressing forms, and you like how it tastes.
Pour the dressing over the kale, and add the mango and pumpkin seeds. Toss and serve.