In a large mixing bowl, combine the all-purpose flour, instant yeast, salt, and sugar.
Add the sunflower seeds, pumpkin seeds, sesame seeds, flaxseeds, and chia seeds to the dry ingredients and stir to distribute evenly.
Pour in the warm water and mix with a wooden spoon or spatula until a sticky dough forms. Ensure all the flour is incorporated; the dough will be wet and shaggy.
Cover the bowl tightly with plastic wrap or a clean kitchen towel and let the dough rest at room temperature for 30 minutes.
After resting, lightly flour a clean surface and turn the dough out onto it. Gently fold the dough over itself 2-3 times to shape it into a rough ball. Do not knead.
Place the dough seam side down on a parchment-lined baking sheet or in a lightly greased round baking pan.
Cover again and let it rise for 10 minutes while you preheat the oven to 425°F (220°C).
Using a sharp knife, make a few shallow slashes on the top of the dough to allow steam to escape.
Bake the bread in the preheated oven for 35-40 minutes, or until the crust is golden brown and the loaf sounds hollow when tapped on the bottom.
Remove the bread from the oven and transfer it to a wire rack to cool completely before slicing.