Preheat oven to 350°F (180°C). Grease the inside of a 9x4 or 8.5x4.5 loaf pan and line with a long strip of parchment leaving some to hang over the edges.

Add the sugar and lemon zest to a bowl of a stand mixer and rub them together until sandy and fragrant. Add the soft butter. Attach bowl to mixer. Using a paddle attachment, beat the butter and sugar together, over medium speed, until creamy, about 2 minutes.

Add the sesame oil and mix to incorporate. Add the eggs, one at a time, and continue beating on medium speed until smooth, about 1 minute.

In a medium bowl, stir together the almond flour, brown rice flour, tapioca starch, sesame seeds, baking powder, salt, xanthan gum, and baking soda.

In a measuring cup, mix the coconut milk and lemon juice. Add the dry ingredients into butter mixture and beat on medium low speed until mixed through, about 30 seconds.

Pour the coconut milk mixture into the batter and beat on medium low until it gets mixed in. Increase speed to medium high and beat for another minute until you have a smooth batter.

Pour the cake batter into the loaf pan and smooth out the top. Run the tip of a knife, lengthwise, through the center of the cake.

Bake for 60 to 65 minutes until golden brown and a toothpick inserted in the center comes out clean.

While the cake is baking, make the glaze. Combine the lemon juice, sugar, and lemon zest in a small saucepan. Bring to a simmer over medium high heat until sugar is dissolved and syrup has thickened. Set aside.

When the cake comes out of the oven, brush the top with the lemon syrup. Let the cake cool in the pan for 15 minutes, then lift out of the pan and transfer to a cooling rack. Cool the cake for at least 30 minutes before slicing.