Preheat the oven to 425 degrees Fahrenheit.

Place the sweet potato pieces on a baking sheet, drizzle with olive oil, and season well with salt and pepper. Roast for 20 minutes.

Meanwhile, prepare the dressing in your serving bowl (you want to use quite a large bowl). Add the yogurt, mayonnaise, honey, and mustard to the bowl, along with the lemon juice and garlic. Mix everything together until well combined.

Once the potato has had 20 minutes, take it out and add the kale and the salmon to the sheet. Drizzle both with olive oil and season with salt and pepper. Use your hands or tongs to toss the kale, squeezing it to soften it slightly as you do. Place back in the oven and roast for an additional 10 minutes.

Once everything is cooked, add the sweet potato and kale to the bowl of dressing. Add the avocado and toss everything together until coated in the dressing. Remove the skin and flake the salmon over the top of the salad in small pieces before serving.