Preheat oven to 400° Fahrenheit and line 2 baking sheets with parchment paper. Mix salt, pepper and garlic powder together in a small bowl.
Prepare sweet potatoes as noted and spread them out on a baking sheet. Drizzle with avocado oil and toss to coat.
Place chicken on the other baking sheet. Season the potatoes and the chicken on both sides with the seasoning mixture. Place chicken and potatoes in the oven to roast until the chicken is cooked through and the potatoes are browned around the edges, approximately 30 minutes. Once finished, remove and set aside to cool.
Heat a small saucepan over medium heat and add cranberries and 1/4 cup of water. Cook, stirring occasionally, until the cranberries start to soften and break down and most of the water has evaporated, about 5-6 minutes.
Carefully transfer cranberries to a blender and add the orange juice, apple cider vinegar, olive oil, maple syrup, water and a pinch of salt. Blend until smooth. If the dressing is too thick, add water, a teaspoon at a time, blending in between additions, until it reaches your preferred consistency.
Chop the cooked chicken breasts into small pieces.
Now, prepare the salad. In a large bowl add spinach, roasted sweet potatoes and chicken. Toss to mix. Serve salad topped with some roasted pumpkin seeds and dressing.