In a small saucepan, heat the milk until just simmering. Remove from heat, add the 3 Earl Grey tea bags, and cover. Let steep for 15 minutes. Squeeze the tea bags well to extract all flavor and discard. Measure out exactly 1/2 cup of the infused milk. Let cool to room temperature.

Preheat your oven to 350°F (175°C). Grease a 9x5-inch loaf pan and line it with parchment paper, leaving an overhang on the long sides for easy removal.

In a medium bowl, whisk together the flour, baking powder, salt, poppy seeds, and finely ground loose Earl Grey tea leaves. Set aside.

In a large bowl or stand mixer, combine the granulated sugar and lemon zest. Rub them together with your fingers until the sugar is fragrant and lightly yellow. Add the softened butter and beat on medium-high speed until light and fluffy, about 3-4 minutes.

Beat in the eggs one at a time, mixing well after each addition and scraping down the sides of the bowl. Beat in the vanilla extract.

Combine the cooled Earl Grey infused milk and the fresh lemon juice (it will curdle slightly like buttermilk; this is fine). With the mixer on low, add the dry ingredients in three parts, alternating with the milk mixture in two parts, beginning and ending with the dry ingredients. Mix just until combined.

Pour the batter into the prepared loaf pan and smooth the top. Bake for 45-55 minutes, or until a toothpick inserted into the center comes out clean or with a few moist crumbs.

Let the loaf cool in the pan for 15 minutes, then use the parchment overhang to carefully lift it onto a wire rack to cool completely.

While the loaf is cooling, whisk together the powdered sugar, strongly brewed Earl Grey tea, and lemon juice until smooth. The glaze should be thick but pourable.

Once the loaf is completely cool, pour the glaze over the top, letting it drip down the sides. Let the glaze set for about 20 minutes before slicing and serving.