Place the grated zucchini in a clean kitchen towel or cheesecloth and squeeze out as much excess moisture as possible. Set aside in a large mixing bowl.
Add the grated carrots and chopped green onions to the bowl with the zucchini. Mix the vegetables together until evenly distributed.
In a separate bowl, whisk together the flour, garlic powder, salt, black pepper, and baking powder.
Add the beaten eggs to the vegetable mixture and stir to combine. Then add the dry ingredients and mix until just combined.
Heat the vegetable oil in a large skillet over medium-high heat until shimmering.
Scoop about 1/4 cup of the mixture and form it into a patty. Place in the hot oil and flatten slightly with a spatula. Cook in batches to avoid overcrowding.
Fry the fritters for 3-4 minutes on the first side until golden brown. Flip carefully and cook for another 3-4 minutes on the second side.
Transfer the cooked fritters to a paper towel-lined plate to drain excess oil. Serve immediately while hot and crispy.
Notes
For best results, squeeze all excess moisture from zucchini. Fritters can be frozen for up to 3 months. Reheat in oven at 350°F for best texture.