Add the sun-dried tomatoes, vinegar, water, maple syrup, oregano, and garlic powder to a small blender. Blend until smooth.
Pour in the olive oil and blend again for 10 seconds until the oil is incorporated. Add more water if needed.
Do a taste test and season with salt and pepper. The amounts needed will depend on your sun-dried tomatoes.
Notes
Dehydrated tomatoes that were not preserved in oil need to be soaked in boiling water for 20 minutes to soften them. Discard the water and blend it with the other ingredients.
Adjustments: The thickness of your dressing really varies with the texture of your sun-dried tomatoes (some are firmer than others). You may need to add more water to obtain a nice pourable dressing.
You can substitute the extra-virgin olive oil with the oil from the sun-dried tomatoes. It's mostly infused with herbs and garlic that give it a really nice flavor, but it's also often a lower-quality oil.
Storage: You can keep this dressing in an airtight container in the refrigerator for 1-2 weeks.
Note that the olive oil will solidify in the fridge but it does not affect the taste of the dressing. Simply take it out of the fridge 10 minutes before serving and give it a good shake.