Seared Tuna with a Kohlrabi Slaw and Ginger-Lime Aioli

Name: Seared Tuna with a Kohlrabi Slaw and Ginger-Lime Aioli
Prep time: 20 min
Cook time: 5 min
Total time: 25 min
Cuisine: American
Ingredients: 1 kohlrabi (peeled, julienned, stored in ice water); 1 apple (cored, julienned, stored in ice water); 12 radishes (thinly sliced, stored in ice water); 1 cup parsley (finely chopped); 2 1/2 tablespoons lemon juice; 1 teaspoon sugar; 1 1/2 tablespoons olive oil; salt & pepper; 3 tablespoons ginger (coarsely shredded); 1/2 cup mayonnaise; 1 garlic clove (minced); 1 lime (juiced); 4 tuna steaks (such as ahi, yellowfin or bluefin); canola oil