Combine all sauce ingredients in a mixing bowl and toss to mix. Let sit for 15 minutes to extract fruit juices.
Transfer fruit to baking dish, bake until fruit is dark and juices are thick, (approximately 15 minutes), stirring occasionally.
Remove from oven. Puree in blender until smooth. Set aside until ready to serve; serve at room temperature.
To make the pancakes, grate potato into mixing bowl. Grate zucchini, squash, and onion into same bowl. Add salt, pepper, garlic, and chives and toss to combine. Let stand for 20 minutes.
In a large, nonstick pan, heat 1 tablespoon of oil and sauté pan over medium heat.
Squeeze potato mixture in a clean, dry tea towel to extract moisture. Divide mixture into 4 portions; sprinkle 2 portions evenly over bottom of pan, spreading with 2 forks to form 2 thin pancakes.
Cook until golden, about 5 minutes. Flip and cook other side until golden brown, about 3 minutes. Repeat with remaining mixture, adding more oil if needed. Drain pancakes well on paper towels after cooking.