Mix yeast with 3/4 cup of warm water, then set aside until foamy.
Combine butter, milk, and syrup in a small saucepan.
Place over low heat until the butter melts --- set aside to cool.
Crush the fennel and anise seeds with a mortar and pestle.
Combine the bread flour, rye, salt, and seeds in a stand mixer bowl.
Once the yeast is ready, pour it into the bowl with the cooled butter and milk mixture.
Mix and knead until you get a smooth dough.
Place your Swedish limpa dough in an oiled bowl, then cover with a clean kitchen towel until it doubles (about 60 to 75 minutes for me).
Uncover, transfer on a countertop, and form it into a loaf about 9 to 10 inches long.
Place it on a baking tray lined with parchment paper, and cover it with a towel until it expands to about twice its size (it generally takes 45 minutes for me).
Preheat your oven to 180°C (350°F).
Uncover your limpa loaf and place it in the lower part of the oven for about 30 to 35 minutes --- or until it turns brown.
As soon as you remove it from the oven, use a pastry brush to glaze the top with syrup.
Let cool for a few minutes, then serve --- your Swedish limpa bread is now ready for slicing!