Preheat the oven to 250°F.

Put the butter in a small saucepan and switch on the heat to low. When the butter has melted, turn off the heat. Let the butter cool slightly (5 minutes).

Meanwhile, open the cans of pineapple. Drain off the juice from the cans into the sink. Set aside.

Put the flour, brown sugar, baking powder, and salt in a large bowl. Stir with a wooden spoon until well mixed.

Break the eggs into a medium bowl. Add the milk and 4 tablespoons of the melted butter. Whisk until well mixed. Slowly whisk in the flour mixture until well blended.

With a pastry brush, lightly brush some of the remaining melted butter in a large skillet. Set the skillet on the stove and switch on the heat to medium-high.

Fill a 1/3-cup measuring cup with batter. When the skillet is hot, after 1 minute or so, pour in the batter. Cook the pancake until golden underneath and bubbles burst on the top, about 3 minutes.

Place 1 pineapple ring in the center of the pancakes. Using a spatula, carefully flip the pancake. Cook until golden brown on the second side, about 2 minutes longer. Transfer the pancake to a baking sheet. Using pot holders, put the sheet in the oven.

Repeat steps 7 and 8, brushing skillet with butter as needed. Serve the pancakes warm with butter and maple syrup.