Have your GH (Grown-Up Helper) heat a medium skillet over medium heat and add the EVOO, 4 turns of the pan. Add the potatoes, season with salt and cook for 5 minutes. Add the onion and cook, stirring occasionally, until the vegetables are softened but not brown, about 15 minutes.
Meanwhile, ask your GH to preheat the broiler. Whisk together the eggs and cream and season with salt. Pour the egg mixture into the skillet and cook until firm around the edges. Have your GH place the skillet under the broiler and cook until the top is firm and golden. Set aside to cool.
Place the bread slices on a baking sheet and have your GH toast them, turning once, under the broiler. Cut the tomatoes in half, then squish and rub their guts all over the bread. Drizzle the bread with EVOO and season with salt.
With the help of your GH, slide the tortilla onto a cutting board and cut into 4 wedges. Serve with the tomato toasts.