Heat the oven to 350°F (177°C). Grease a 9x5-inch loaf pan, line the bottom with a parchment strip that overhangs the long sides, and lightly butter the parchment.
Whisk together the flour, baking powder, and salt in a medium bowl; set aside.
In a large bowl, beat the softened butter and granulated sugar until creamy and lighter in color, about 2 to 3 minutes using a hand mixer or sturdy whisk.
Add the eggs one at a time, whisking until each is incorporated before adding the next. Stir in the vanilla and almond extracts and the lemon zest.
Reduce the mixer speed (or slow your stirring) and fold in about one-third of the dry ingredients, followed by half of the coconut milk. Continue alternating additions, finishing with the remaining flour just until no streaks remain. Be careful not to overmix.
Use a spatula to fold in the shredded coconut evenly through the batter.
Transfer the batter into the prepared pan, smooth the top, and tap the pan once on the counter to settle the batter. Bake in the center of the oven for 50 to 65 minutes. Start checking at 45 minutes: the loaf is done when the top is golden and a skewer inserted into the center comes out mostly clean with a few moist crumbs.
Let the loaf cool in the pan on a wire rack for 15 to 20 minutes. Lift the cake out using the parchment overhang and set it directly on the rack. Cool another 25 to 30 minutes until warm but not hot (this helps the glaze adhere without melting away).
While the cake cools, whisk together the confectioners' sugar, coconut milk, and vanilla until smooth and pourable. If the glaze is too thick, add a teaspoon more coconut milk; if too thin, add a tablespoon more sugar.
Drizzle the glaze over the slightly-warm loaf so it sets with a sheen. Immediately sprinkle the reserved shredded coconut over the top (and a tiny pinch of extra lemon zest if you like). Allow the glaze to fully set for 20 to 30 minutes before slicing.