Candy Pecans: Heat a medium pan over medium heat. When the pan is hot, add pecans. Toast for 4-6 min, stirring occasionally, until pecans are browned. Remove the pan from heat. Drizzle 1 tbsp maple syrup over top. Season with salt. Stir to coat. Transfer to a parchment-lined plate or pan to cool.
Make Dressing: To a glass measuring cup or jar, add blueberry jam or maple syrup, vinegar, garlic, Dijon and oil. Season with salt and pepper, then whisk to combine.
Assemble & Serve: To a large bowl or serving platter, add spinach, blueberries, onions, cucumbers and basil. Drizzle dressing over top, then toss to combine. Season with salt and pepper, to taste.
Serve: Top with pecans and avocado or transfer to 4 serving bowls and top each with equal amounts of the pecans and avocado.