Heat the oven to 200°F. Place the almond paste in the bowl of an electric mixer fitted with the whisk attachment. Whisk on low speed while adding the milk, a little at a time, to loosen up the paste until it’s smooth and not lumpy. Alternatively, you can process the almond paste with a little of the milk in a food processor until smooth (add just enough milk to help the almond paste thin out).
Add the sour cream, almond extract, and eggs. Whisk or process until well-blended and smooth.
In a large mixing bowl, add the flour, sugar, baking powder, salt, and poppy seeds. Whisk well to thoroughly combine.
Slowly pour the liquid ingredients into the dry ingredients while gently stirring, and mix just until combined. (Don’t overmix or you will activate the gluten in the flour and the pancakes will be chewy, like bread, instead of fluffy.) The mixture will be a little lumpy (and that’s OK; if you have pockets of flour bigger than a dime, smash them against the side of the bowl to break them apart without having to stir the batter more). Pour in the melted butter and gently mix just until incorporated. (Sometimes melted butter solidifies when added to cold ingredients. Adding it now helps disperse it evenly in the batter and smooth out some of the lumps.)
Place a griddle or wide (preferably 14-inch) sauté pan over medium heat for several minutes. If using an electric griddle, set the heat to 350°F.
Sprinkle the griddle with a few drops of water; they should bounce around before evaporating. If they sizzle away quickly, the heat is too high. If they just sit there and slowly steam, the heat is too low. When the griddle is properly heated, brush with oil or clarified butter, and then wipe with a paper towel so it’s evenly greased. (Big spots of oil or butter will promote uneven browning and your pancakes will have dark and light spots.)
Ladle 1/2 cup of batter per pancake onto the griddle, an inch or two apart. Sprinkle evenly with 1 Tbs. toasted almonds.
Cook until bubbles begin to pop on the surface of the pancakes, the edges look a little dry, and the underside is golden, about 2 minutes. Flip them over and continue cooking until the pancakes are cooked through, about 1 minute more. (If the undersides of the pancakes are browning or burning before the tops get a chance to form bubbles and dry out, the heat is too high. If it’s taking much longer than 2 or 3 minutes for the bubbles to form, the heat is too low.)
Repeat with the remaining batter. Keep the pancakes warm on a heatproof platter or baking sheet in the oven.
Serve with whipped butter and maple syrup.