Take one bowl, mix dry ingredients and in another bowl mix wet ingredients.
Add dry ingredients to wet ingredients slowly, whisk both mixtures together until batter becomes smooth, cover and keep aside for 30-45 minutes.
Warm a nonstick pan over medium heat, lightly grease with oil and pour about 1 big spoon of crepe batter and spread it out thinly. Cook until edges are golden and then flip to cook on the other side, repeat with remaining batter.
for sour cream
Put the yogurt in a muslin cloth and hang it to remove the extra moisture for approximately 30 minutes.
Take a bowl, add hung curd and cream. Mix it till it becomes smooth and add pinch of salt.
If you want, you can add lemon juice. Mix it well.
for stuffing & sour cream mixture
Stir sour cream, milk, lemon juice, salt and chopped parsley in a bowl, until combined and keep it aside.
Heat oil in a large nonstick pan over medium heat, add zucchini, bell peppers and sauté until brown (about 6-8 minutes). Reduce heat to low, add salt, pepper, and 1/2 cup sour cream mixture, stirring gently and remove it from the heat.
To roll crepes, place one crepe on kitchen board or plate and put 2-3 tbsp of vegetable mixture on the centre of the crepe. Gently roll the crepe around the stuffing. Finally place the crepe on a serving plate, repeat with the remaining crepes and stuffing.
Serve crepe with sour cream OR
Serve each crepe topped with 2 tbsp of the sour cream mixture.