Preheat oven to 175 degrees Celsius (350 degrees Fahrenheit)
Heat the olive oil in a pan on medium-low heat. Cut the onions into thin slices and place in the heated pan and sprinkle with 1/4 tsp salt. Cover the pan and cook, stirring occassionaly until the onions have wilted. If they begin to burn/brown too quickly, lower the heat. Cook for approximately 20-25 minutes until they have turned golden in colour and caramelized.
In an electric mixing bowl combine the almond flour, eggs, butter, baking soda, apple cider vinegar and nutritional yeast, Mix until well combined.
Place on a baking sheet and form into a loaf approximately 1 1/2 - 2 inches thick. Top with the caramelized onions, chopped thyme and salt.
Bake in the oven for 20-25 minutes or until the bread is golden brown in colour. Allow to cool before slicing.