Preheat the oven to 175°C (350°F, gas mark 4), and line a 20cm x 20cm (8"x8") baking tray with non-stick parchment or a silicone mat.
While the oven is heating, make the glaze: Heat the oil in a skillet over a medium-low heat, and gently fry the garlic for 4-5 mins, until the raw smell has gone.
Dilute the tomato purée with the water, and whisk in the sugar, balsamic, liquid smoke, soy sauce, mustard powder, tamarind, and Tabasco.
Add to the skillet, stir well, bring to the boil, then turn down to your hob's lowest heat, and allow to simmer until the sugar has dissolved (you may need to stir it occasionally). This should take around 5 mins. Once the glaze is done, set aside.
Make the 'ribs' by blitzing the wet ingredients in a blender for 30 seconds or so.
Place the dry ingredients into a large bowl, and stir.
Add the contents of the blender to the bowl, and mix well, until all the dry ingredients have become incorporated.
Lightly knead for five minutes or so, to activate the gluten, then stretch out the dough so that it fills the baking tray.
Take a sharp knife and score the dough into 12 equal pieces (6 x 2) - you don't need to cut them all the way through.
Brush the top with a some BBQ glaze, lightly cover with foil, and bake for 30-35 mins, until springy to the touch.
Remove the baking tray from the oven, and set aside for a couple of minutes.
Turn on the grill (broiler), and brush the grill rack with oil to prevent sticking. Remove the seitan ribs from the baking tray, brush more glaze over the top, and place under the hot grill.
Once the top starts to caramelise, flip over, brush with more glaze, and repeat.
When they're done, cut along the score lines, and serve immediately.
If using a grill pan on the hob: heat the pan over a medium heat, and brush with a little vegetable oil.
Remove the ribs from the baking tray, and brush the top with more glaze, carefully turn out onto the grill, and then brush the new topmost side with glaze. As soon as the bottom of the ribs start to caramelise, flip over, and grill the other side.
If you're having a barbecue, you can finish the ribs off on the grill - obviously removing them from the baking tray first! Follow the instructions for using a grill pan.
Use liquid coconut aminos if avoiding soy.
Use chickpea flour (aka garbanzo bean flour or besan) instead of buckwheat.
Tomato purée is also known as tomato paste.
Use a tablespoon of smoked paprika instead of liquid smoke, if you prefer.
If you have a food processor, fit the blade, add the dry ingredients, then the blended wet stuff, and process on high speed for 3-5 minutes, until the dough becomes elastic.
Electric grills and panino presses work really well too, and mean you don't have to turn the ribs over!