Prepare the honey syrup. In a small saucepan, combine the sugar, water, and cinnamon stick and simmer the syrup on low heat. Once the sugar dissolves, add in the honey, pure vanilla extract, orange zest, and honey. Continue to simmer on low heat for 5-7 minutes bringing the syrup to a light boil. Then, add in the lemon juice. Continue to stir the syrup for another minute or two and then remove from the heat and set aside to cool.
Preheat your oven to 350 degrees F on bake.
In a large bowl, add 4 eggs and mix the eggs with an electric hand mixer on medium speed until they're fluffy and a pale yellow colour. If you don't have an electric hand mixer, you can use a whisk or an electric stand mixer with a whisk attachment.
Gradually add the sugar and vanilla extract to the eggs and continue to whisk together until well mixed. Then add the oil, oat milk, and orange zest.
Sift 2 cups of all-purpose flour into a separate medium-size bowl. Add in the cinnamon, baking soda, and pinch of salt, and mix the dry ingredients well together.
Slowly add all of the flour mixture to the wet ingredients and mix together using a large spoon.
Grease a 9" fluted bundt cake pan or 10x2 inch square pan with a little bit of oil or butter. Dust with flour or line with parchment paper. Pour the cake batter into the cake pan. Tap the cake pan lightly on the counter to remove any air bubbles.
Place the cake inside the preheated oven and bake for 40-45 minutes. The total baking time may vary depending on your oven. To see if the cake is done, insert a toothpick into the cake. If the toothpick comes out with a few moist crumbs, then your cake is done.
Remove the cake from the oven and slowly pour the room temperature honey syrup over the top of the cake while the cake is still hot and in the cake pan. Once the cake has absorbed the first bit of syrup, pour the remainder of the syrup evenly over the cake.
This is where you'll have to be patient - the hardest part! The cake should sit with the syrup in the cake pan for at least an hour at room temperature to absorb all of the delicious honey syrup.
When you're ready to serve the cake, flip the cake over onto a cake stand or plate and sprinkle it with icing sugar. If the cake doesn't come out easily at first, use a butter knife and lightly scrape around the edges of the cake.
Sprinkle with icing sugar.