Leave the eggs and butter outside to have them at room temperature.
Grind 6-8 pods of green cardamom along with their skin for a fresh aromatic taste.
If your xanthan gum is in crystal form, make a fine powder in a small blender.
Grease a baking dish (about 9" inch in radius), line it with parchment paper and set aside.
Pre-heat oven to 350 deg F.
The Batter:
Sieve together the sorghum flour, almond flour, baking powder, and salt.
Add Xanthan Gum and sieve. (Pic#2), also add in cardamom powder.
Make sure your butter is softened, if not microwave it for 10-20 seconds. In a stand mixer or in a bowl using a hand blender, whisk together butter and white sugar for about 2-3 minutes to get a white fluffy mix.
Add brown sugar and blend it well.
Add the egg white of one egg and three whole eggs. Also add 1 tsp vanilla extract.
Blend the eggs until well combined and fluffy (Pic#5). Add the vegetable oil and blend well.
Make a well in the center of the dry mix and pour in the wet mix.
Using a spatula, mix well, taking care not to over mix. Pour the batter into the lined baking dish.
Sprinkle sliced almonds (optional)
Baking:
Place the dish in the center rack and bake in the oven for about 40 minutes.
Check for readiness by inserting a toothpick/ skewer in the center. If it comes out clean, turn off the oven and let the baking dish be in the oven for 4-5 minutes.