Spray a 8x8 square cake pan with baking spray and then line with parchment paper. Then pre-heat your oven to 350F.
In a large bowl crack in the two eggs and whisk until frothy. About 1 minute. Now add in the ¼ cup each of calamansi juice, olive oil, sour cream and honey. Mix well.
Add in the vanilla cake mix. Mix lightly until there are no more lumps. Try to not over mix it.
Pour it into the prepared pan and bake for 25-30 minutes. To check if it's done use a dry toothpick to poke through the middle of the cake. If it's clean the cake is done. If there is some raw batter still stuck, bake for 2 minutes more until there is no more raw cake batter on the toothpick every time you check the doneness.
Once your Calamansi Olive Oil cake is baked. Turn on the broiler and broil the top of the cake until it's a nice dark brown color. About 1 minute. Then take out of the oven.
Place plastic wrap on top of a cutting board and then invert that over the cake pan. Flip over the cake and remove the parchment paper. Wrap the cake in plastic wrap while it is still warm. This will also help the cake stay nice and moist for several days.
Ideally you should wait until the next day to cut, But if you are in a hurry to try the cake make sure it is at least fully cooled down. Probably wait at least 1-2 hours before cutting your cake. To cut slice the cake down the middle and then cut each half into 5 slices.