Heat a large wok or pan with a little oil over a medium-high heat; add the minced garlic and chicken and cook for 1 minute.
Add the oregano and red wine vinegar and continue to cook the chicken until it is almost done; then set aside in a bowl. The key to cooking tender chicken is to slightly undercook it. Meat continues to cook while it is still warm. If you're unsure, break one of the strips in half and you will see if it's still pink inside, or if it's cooked.
Next, add a little more oil to the pan; along with the spring onion (scallions), tomato, red bell pepper and cook for 1 minute.
Stir in the zucchini noodles and give it about 2 minutes to cook; stirring occasionally. If you like the noodles cooked more, then continue to cook a little longer but they work very well if they are crisp.
Stir the chicken back through the dish and turn off the heat.
Serve in 2 bowls and top with a little grated cheddar and a spoonful of sour cream.