Preheat the oven to 350°F. Generously coat a 9x5x3-inch loaf pan with vegetable oil spray or softened butter.

In a medium mixing bowl, vigorously whisk together the all-purpose flour, baking powder, ground nutmeg, and kosher salt to ensure the leavening agents are perfectly distributed.

In the bowl of an electric mixer, combine the whole milk, canola oil, and granulated sugar, beating until fully emulsified.

Add the eggs one at a time, mixing thoroughly after each addition. Stir in the almond and vanilla extracts.

Reduce the mixer speed to low. Gradually add the dry flour mixture, mixing only until just combined to prevent overworking the gluten, which leads to a tough crumb.

Using a rubber spatula, gently fold the poppy seeds and fresh blueberries into the batter by hand to prevent the fruit from crushing and bleeding into the dough.

Pour the thick batter into the prepared loaf pan, smoothing the top.

Bake in the preheated oven for exactly 1 hour, or until the loaf is deeply golden brown on top and a wooden tester inserted into the center comes out perfectly clean.

Allow the loaf to cool in the pan on a wire rack for 10 minutes before carefully turning it out to cool completely.

While the loaf bakes, place the fresh blueberries, blackberries, granulated sugar, lime zest, and lime juice into a medium saucepan over medium heat.

Cook the mixture, stirring occasionally, until the berries begin to burst and turn mushy, about 10 to 15 minutes.

Stir in the chopped fresh mint and continue to cook until the berries break down completely into a thick, glossy syrup, about 5 minutes more.

Pour the hot jam into a heat-proof bowl or crystal jar and allow it to cool to room temperature where it will continue to thicken and set. Serve heavily slathered over thick slices of the warm poppy seed loaf.