Once your poblano chiles are roasted and peeled, using a knife, make a vertical cut from the stem to the tip of the chile.
Fill with your favorite vegan cheese, close the chile, and secure with toothpicks. Set aside.
To make the sauce: Place the tomatoes, garlic, and onion in the blender and process until smooth.
Heat a medium sauce pot to medium heat and add the tomato sauce. Simmer for 7 – 10 minutes or until the sauce begins to thicken. Season with salt and pepper. Set aside.
To make the batter: combine the flour, chickpea flour, cornstarch, and salt in a large bowl. Pour in soda water gradually and whisk, until the batter reaches the consistency of a thin pancake batter.
Heat three inches of oil in a high sided pan to 360°F. Dip each chile into the batter, letting excess drip off, then place in oil and fry until golden, about 5 minutes on each side.
Remove the chiles and place on a plate lined with paper towels to absorb excess oil.
Serve the chile on top of a plate of the tomato sauce