Preheat the oven to 350ºF and set oven racks to the middle.
In a small bowl, combine the flax meal and water to make flax egg. Set aside.
In a small saucepan, add the blood-orange pieces and sugar. Bring to a boil on medium-high heat. Simmer on medium-low for 5mins. Turn off the stove. Using a handheld blender, blend the orange mixture until the mixture is pulpy but not chunky. Pour the mixture through a sieve and separate the liquid into a separate bowl. Save the pulp remains.
In a large bowl, sift together flour, sugar, baking powder and salt.
In a small bowl, whisk together the plant milk, vegetable oil, almond extract and flax egg.
Make a well in the dry mixture and pour in the wet mixture. Using a spatula or wooden spoon, mix until just combined. Add the almond slices and mix until the almond is evenly distributed in the batter.
Lightly oil and line a loaf pan with parchment paper. Pour in half of the dough and spread it out on the bottom of the pan. Add the orange pulp and evenly distribute on top of the dough. Pour in the remaining batter and smooth it out on top of the orange pulp.
Bake for 45-50mins, or until the top is golden brown and a toothpick comes out clean.
Meanwhile, make the glaze by whisking together sifted icing sugar and 5 tbsp of the orange juice from the purée.
Allow the loaf to cool for 5mins before taking it out of the loaf pan, Allow the loaf to cool completely on a cooling rack before pouring on the glaze.