Preheat oven to 350°F (175°C) and line a large baking sheet with parchment paper.
In a medium bowl, combine 1 cup rice flour, 0.5 teaspoon salt, and 1 tablespoon sesame seeds (optional).
Gradually add 0.5 cup warm water and mix until a shaggy dough forms.
Add 1 tablespoon vegetable or canola oil and knead in the bowl until the dough is smooth and no longer sticky, adjusting with water or rice flour if needed.
Divide dough into two equal portions.
On a lightly floured surface, roll one portion of dough as thinly as possible (about 1/16 inch).
Cut the rolled dough into desired shapes with a knife, pizza cutter, or cookie cutters.
Transfer crackers to the prepared baking sheet, spacing them apart.
Bake for 15–20 minutes, until golden brown and firm to the touch, watching closely toward the end.
Let crackers cool completely on a wire rack to crisp up.
Repeat rolling, cutting, and baking with the second dough portion.