Preheat the oven to 220C, fan-forced. Line an oven tray with baking paper. Thinly slice the onion. Cut the tomato into thin wedges. Pick the parsley leaves, then finely chop the stems. Crumble the feta into a large bowl.
Step 2 — Marinate tomato
Combine 1 tbs olive oil, 2 tsp red wine vinegar and ½ tsp sugar in a large bowl. Add the tomato, parsley stems and half the onion (see Make it yours), season with salt and pepper and stir to combine. Set aside to marinate, stirring occasionally, until needed.
Step 3 — Make filling
Meanwhile, heat 2 tsp olive oil in a small frypan over medium heat. Cook the remaining onion, stirring, for 3-4 mins until softened. Remove from the pan. Add the onion and spinach to the feta and stir to combine.
Step 4 — Bake melts
Halve the baguettes lengthwise and put, cut-side up, on the lined tray. Spoon the spinach mixture over the baguette bases, then scatter over the shredded cheese. Bake for 5-7 mins until the cheese is melted and the baguettes are crisp. Sandwich with the baguette tops.
Step 5 — Serve up
Stir the parsley leaves into the tomato salad. Divide the spanakopita melts and tomato salad among plates and enjoy!
Step 6 — Make it yours
Marinating the raw onion mellows the flavour. If you prefer, leave it out of the tomato salad and cook it all in Step 3 instead. ~ Serve the tomato salad on the side or, for a tangy hit, pop some into the melt.