Warm the bread for 5-10 seconds on a heat-safe plate In the microwave. (This Is optional, but Is recommended If your bread Is not super soft and at room temperature. You can also warm It longer If you're starting with frozen bread slices.)
Place the bread onto a cutting board and roll very flat with a rolling pin.
Spread on the fillings to the edges of the bread.
Roll up, starting at the base of one of the long sides of the bread (the bottom of the slice). Try to make the roll tight, but roll gently to avoid pushing all of the filling out.
Slice gently with a serrated knife. I usually slice the rolls so they are about 1-Inch thick.
Serve or pack In a lunch box.
Notes
You can make these up to 24 hours ahead and store in an airtight container or lunchbox in the fridge. Pack them tightly in the container so they are nestled up against each other, which will help them hold together.
A soft sandwich bread works best here. A whole grain bread is fine (though this is not a great use for a hearty artisanal bread with a lot of seeds).
Warming the bread just slightly can help it flatten more easily.
A serrated knife is key for easy slicing.
Try peanut butter and jelly, sunflower seed butter and jam, apple butter, cream cheese and jam, nutella, turkey, cheese and mustard, hummus, or any other filling or spread you like.
Keep the layer of filling fairly thin so it's easy to roll.
I keep the crust on to save a step, though you could remove them if you prefer.
You can make these the night before you plan to serve them and store in an airtight container or lunchbox in the fridge.