Combine poppy seeds, sesame seeds, garlic flakes and onion flakes in a small pan and set over medium heat. Toast for 2-3 minutes until golden. Remove from heat and set aside to cool.

Line slow cooker with parchment paper.

Combine beans and milk in a blender and blend until smooth. Set aside.

In a large bowl, combine flour, baking powder, baking soda, and salt. Coarsely grate frozen butter into the bowl and use your hands or a fork to combine until butter is well incorporated and crumbly.

Make a well in the center of the dry ingredients and pour in the bean mixture. Use your hands to mix into a ragged dough. Continue to gently mix the dough by hand for 1-2 minutes, or until the dough comes together. If the dough feels tough, add a little more milk, a tablespoon at a time until it softens. (The dough will not be completely smooth.)

Turn the dough onto a floured surface and roll into a large 12×18-inch (30×45 cm) rectangle, with the long side facing you. Sprinkle half of the cheese over the rectangle, leaving a 1-inch (2.5 cm) border on the opposite long side to you.

Set aside 2 Tbsp (30 mL) of the toasted seeds for topping, then sprinkle the rest in an even layer over the cheese, followed by the prosciutto and then the remaining cheese. Roll the dough up into a roll, starting on the side closest to you, then gently squeeze to seal.

Use a sharp knife to cut the roll into 10 slices. Place the rolls in the prepared slow cooker, cut side down. Brush the tops with melted butter.

Place a paper towel underneath the slow cooker lid to help absorb condensation (do not skip this step, and do not use a cloth towel!) Secure the slow cooker lid and cook for 2-2 ½ hours on high.

When buns are done, immediately remove them from the slow cooker, using the parchment paper to lift. Sprinkle with green onion and reserved toasted seeds. Enjoy warm!

tips

• If you don’t have Great Northern beans, you can also use White Kidney or Cannellini beans instead.
• If you like the tops of your pastry more crispy and golden, transfer the rolls in the parchment to a baking dish once they are done cooking, and place them in the oven for 5-10 minutes at 300°F.