Preparation

• Toss the cherry tomatoes with some olive oil and salt and pepper. Roast them, cut side up, at 275°F for about 25 minutes. You don;t want them to dry out completely.
  Chop the thyme leaves and toss with the thinly sliced white onions adding some olive oil, salt and pepper.
  Put this in a large pan and cook on high for about a minute, then reduce the heat to low and cook for about 25 minutes until the onion is light brown and sweet.
  Mix in 1/2 teaspoon of white wine vinegar.
  When the tomatoes are cooked, set them aside. Increase the oven temperature to 325F.
  
  Make the Socca batter with your chickpea flour.
  Combine 1 3/4 cups chickpea flour, 2 cups water, 1 1/2 tablespoons olive oil and 3/4 teaspoon salt plus a grind of pepper in a bowl and whisk by hand until smooth and well combined.
  
  In a separate bowl, whisk two egg whites to soft peaks and then gently fold them into the batter. Now line a baking sheet with parchment and set aside to put your pancakes on as you make them.
  
  Use a small 6″ pan to fry the pancakes or a regular non-stick frying pan, keeping the pancakes about 6 ” in diameter. Put a bit of olive oil in the pan, the pour the batter about 1/4 ” thick and then just wait for the bubble to start appearing on the top. Give it a flip and cook for about another minute and pop onto the parchment lined cookie sheet. Make the rest of the pancakes (4-6 total) and then put them all in the oven for 5 minutes.
  
  Top the pancakes generously with the caramelized onion and then add the tomatoes. You can warm this in the oven for a few minutes before serving.
  The crème fraîche can be served on the side.